Radio on a boat.          Please send any comments to me.

This page updated: August 2012
      




Radio Types section
What Radio To Get For Boat section
Phone On Boat section
Getting Started in Ham Radio section
Ham Radio Operation section
Weatherfax section
Email section
Content section
Licenses For USA Boat section
Installation and Operation On Boat section
Radio-Frequency Interference (RFI) section
Web Access From Boat section
Signals section





Radio Types


There are many radio frequency bands (LF, HF, VHF, UHF, etc),
modulation modes (AM, FM, FM SSB, etc),
and information types (Morse, voice, digital, etc).
See the Signals section of this page for a little more info.

"Ham radio" can use many combinations of these bands, modes and types.
"Shortwave" also covers a number of bands, modes and types.
But non-Hams use just a few combinations, which go by common names including "Marine VHF", "Marine SSB", "Citizens Band", etc.

Commonly-named radio types:
Type and Cost Power/Range Etc
Marine VHF
$80 - $500
25 watts.
5 - 40 miles.
Line of sight.
Antenna height is key.
Channel 16 monitored by USCG.
Only legal for ship-to-ship and to a few kinds of shore facilities.
VHF, FM, voice.
SailNet - Sue and Larry's "VHF Radio: Usage And Etiquette"
Answers.com "Marine VHF Radio"
Don Casey's "Marine VHF Basics"
Marine Single SideBand (SSB)
$1100 - $1650,
plus $500 for antenna tuner and cable,
plus $200 for antenna.
150 watts.
1000 miles or more.
2182 KHz for emergencies.
Legal to use only for ship-to-ship and to a few kinds of shore facilities.
Can connect to phone system through WLO ($4 - $5 per minute).
Can connect to email through a TNC ($350 - $1100).
Can add weatherfax for $2000 (West Marine) or cheap software and PC.
HF, suppressed carrier AM SSB (USB), voice or digital.
Shortwave
Receivers $100 - $1000 (decent one for $400).
Medium Wave Circle "Receiver Reviews"
"The Shortwave Store"
Range can be worldwide for some frequency bands and conditions.
Range better at night.
Receive only.
Lots of broadcasting.
HF, AM, voice ?
Audio quality similar to AM radio.
Ham (Amateur Radio) Various power limits from 50 to 1500 watts.
Range can be worldwide for some frequency bands and conditions.
Amateur broadcasting on various frequency bands (including shortwave) with various power limits.
License required.
Different license levels give access to different frequency bands.
Music, broadcasting, earning money not allowed.
ARRL
FCC form 605 and RF Safety Certification.
Citizens Band (CB) 4 watts (carrier power).
< 150 miles.
Voice only (channel 9 for emergency only).
40 channels.
No license required.
No music or advertising or for-pay traffic allowed.
Not allowed to communicate more than 155 miles or across borders.
Family Radio Service (FRS)
$50 - $200 each station.
1/2 to 4 watts.
1/2 to 2 miles typical.
Line of sight.
Any use.
546 channels.
No license required.
Can have scrambler or privacy code (not very secure).
Can't broadcast; only talks between your two stations.
Legal in USA and Canada only.
Cell-phone
(digital or analog)
Up to 10 miles from nearest tower.
Towers mainly limited to coast of USA.
Analog has higher signal strength than digital.
Built-in has higher power than handheld.
External antenna helps. Can buy signal booster / range-extender too.
Any use.
Data speed is slow (9600 baud for digital, 2400 for analog).
Satellite phone
Monthly fee plus > $1 per minute.
Varies by vendor and your location. Any use.
"With some terminals the data rate is up to 64 Kbps".
Satellite radio
Monthly fee, such as $10/month for 100 channels.
??? Broadcast-only; you can receive only.
Weather, music, news, entertainment, etc.
Receiver about $150.






What Radio To Get For Boat


SailNet - Sue and Larry's "Communications From Aboard"
"Communications Options" survey article in 5/15/2002 issue of Practical Sailor.
Long Passages' "Communications"
BoatU.S.'s "VHF Radios: Why You Need One" (surveys many types of radio)
VHF radios tested in 8/1/2001 issue of Practical Sailor
SailNet - Jim Sexton's "Frequently Asked [Marine] SSB / Ham Questions"
SailNet - Jim Sexton's "Marine Radios Overview"
Satellite phone and HF email articles in Feb 2002 issue of Blue Water Sailing magazine
Satellite phone article by Chris Parker in Jan/Feb 2008 issue of Ocean Navigator magazine
"Email at Sea" article by Dan Piltch and Tim Hasson in Sept 2004 issue of Ocean Navigator magazine
Jim and Diane's "Electronics and Communications"
SailNet - Kathy Barron's "High-Frequency Radio Basics"
Article by Tim Hasson and Dan Piltch in Feb 2004 issue of Blue Water Sailing magazine
FRS radios tested in 1/1/2002 issue of Practical Sailor
Book: Marti Brown's "Marine SSB Radio For Idi-Yachts" (on Amazon)

From Dave Richardson on the WorldCruising mailing list, in response to someone who was "not going to invest in a Marine SSB rig":
... stay safely tucked in when its anything over force 4. Not batting your head into the trades at force 5 will save you more $$ with your boat than any money spent on Marine SSB or Fax. Life can be grand this way.

If saving $$ by not investing in Marine SSB is a primary concern then let me also contribute a contrarian view. Don't invest in weatherfax either. You will spend a huge amount of time in tuning and trying to interpret the information that is better spent listening to experts on NWS. Listen to the NWS "Offshore Forecast". You will be interested in the Southwest North Atlantic Zone and the Eastern Caribbean Zone. These are updated and transmitted every six hours. You will have 12, 24, 48 and 72 hour forecasts which are about all you can hope for anyway. Next, they will have been interpreted by an "expert" who is paid by your government to create effective information from esoteric weatherfaxes. With a week of these on your chart table you will have a very effective record of weather trends. All this can be done with either a Grundig or a Sony [shortwave receiver]. The antenna is more important to good reception. But also invest in a pair of earphones ($5) as there is nothing worse than listening to the 0530 AST NWS with your mate still in the sack. She will not be happy with either a Sony, Grundig or even an ICOM (Marine SSB) at that hour.

Second, take a good barometer and record readings hourly with your navigation log. This is the best local trend information you can find.
But then from John on the same mailing list:
I second Dave's advice, but you may want to consider that if you will be taking a laptop anyway, wefax software will allow you to silently download the NWS forecasts in text format.

From Jerry King on Cruising World message board:
HF comms are still the BEST:

A couple of reasons why I think SSB/Ham technology is still the preferred long-distance communications method:

1) I can send/receive e-mail at 11K bytes/minute, e.g. a three page letter in one minute. It is FREE and very easy!!

2) There is an enormous community of Hams who want to help boaters. During the three years we were in Mexico I made several FREE phone patches (phone calls via HF radio on my end and a standard phone line on the other end) per week to parents, friends, wife, siblings all over the US. A phone patch works almost perfectly and is almost transparent (other than saying OVER) to the folks on the land line.

3) Winlink 2000 has a fantastic array of weather data that can be sent to your HF radio/PC. Any free weather data that is available on the Web can be sent automatically to your boat. I could receive a crystal clear weatherfax in less than two minutes.

4) When you need help, e.g. on the beach in a hurricane, there is ALWAYS a Ham available to talk to. There is a highly organized community that listens 24 hours per day for HF emergency traffic. They have detailed and well practised prodedures that have been pre-coordinated with the USCG and other rescue agencies.

5) Using Winlink I can send e-mail directly to another boat who is also winlink equipped. For example I can send a chart, via e-mail, to a friend who is in an unexpected area with no chart. Or, the picture of the entrance to a cove they have never entered. Or, the schematics for a fuel pump ... etc.

6) SSB and Ham nets are wonderful ways to stay in touch with friends as you cruise. For example in Western Mexico my friends were often 200 - 500 miles distant. I could meet them on a morning, noon, or evening net, take them off to an open frequency or channel, and talk for as long as I wanted. We could coordinate plans, gossip, or complain.

7) When you need medical, mechanical, "where to find" help, the nets will almost always get you the information within hours.

From sded on Cruising World message board:
Satcoms and HF radio really excel in different niches.

... Satcom: ... Generally these systems are designed to provide reliable telco-like point-to-point communications far more effectively than HF radio. If what you want to do is phone home, get calls, pick up small amounts of specific data, a satcom system is the way to go.

What these systems don't do well and the HF radio nets do very well is provide a broadcast or BBS-type capability for those with common interests and problems with immediate needs for solutions. ... If you want to know what is happening out there now, get an HF radio and tune in to the nets. And you can even use it for email and individual calls, although not as efficiently as satcoms. ...

Ham versus Marine SSB:
From RickM on the WorldCruising mailing list:
I have a 4 year old Yaesu Ham radio on board. It's held up well and meets all my requirements for HF communications. Cost for the radio and tuner were 50% of a comparable marine SSB. Installation costs (grounding, backstay insulators) were the same. I can receive weatherfax, operate on the cruising nets and send email (once I get the hardware).

The two downsides I see for Ham rigs on a boat are corrosion and ease of use. The marine SSB's have less gizmos (knobs, filters, meters, etc) and operate more like a Marine VHF radio. The Ham rigs require more tweaking to get the same performance. As far as corrosion goes, the marine SSB's are better suited to life on a boat. I've seen some corrosion problems on my set. Cruising buddies with marine SSB's have not seen this problem on their rigs.

From Michael Homsany:
Price differences on Marine SSB compared to ham rigs:
There was a time when the Marine SSB rig was more costly because of the difficulties of maintaining frequency accuracy in the channelization scheme. This hasn't been true for years. I think it's more a question of 'what the market will bear'. Power outputs on exciters are the same, as in some cases, the radio is the same, just different covers and software! That's also why so many rigs can be 'easily modified'. I used to have a Yaesu FT-23r 2-meter handheld, the exact same radio was marketed with (different numbers on it) to varying public-safety VHF users. A dead give-away for this type of radio is the presence of a 'cloning' feature: it's how the mfg downloads the channelization scheme for the service the radio is marketed into. And you thought the automakers were bad with the chrome trim ...

From Brian Sawyer on Cruising World message board:
Marine SSB (WCP7083) vs ham (KC5YSP): I have an Icom 710 on board that will go both ways. I went to the trouble to get my no-code technicians license but I have never once needed it. All the weather nets that I have wanted to access were on Marine SSB. WOM (for telephone connections and weather) is on Marine SSB and I just don't keep radio schedules to talk to buddies. The weatherfax data comes in on Marine SSB too.

From Chris Waln on Cruising World message board:
... I have great respect for Hams and the public services they render ... [but]

What I'm after is access to data and the ability to calm the fears of family who have no appreciation for us being out of sight of land ...

The Marine SSB gets me the data -- WX, WXFAX, NAVTEX and e-mail -- if I have to talk to someone ashore, I can get voice as well.

Ham, given I don't even like to turn on the Marine VHF, doesn't make sense for me. It's a lot of extra work and expense for very little marginal value to the way we cruise.

From Ray Thackeray on the WorldCruising mailing list:
When I upgrade my rig, it will be to an SGC (for Ham and Marine SSB). The reason is that all the Ham rigs are next to unusable by the casual user. I have been an amateur radio enthusiast since I first got my license at 16 in England (over 28 years ago ... !) and because I don't use the rig regularly (usually when actually sailing), I virtually have to read the manual EVERY TIME I USE THE RIG. Even on a voyage of 8 weeks non-stop, using the rig every day, I still had problems with tuning with the knob, locking the dial, selecting the right mode, etc.

A Ham rig does not give the marine [SSB or VHF] channel numbers - except the minority of dual units - and are designed with an arcane user interface for the dedicated Ham.

This means that the rig is almost unusable by the average crewmember. The SGC, however, is much simpler to use, keying in the frequency/channel, selecting correct SSB mode, etc.

On my Ham rig, I still can never remember if I should be in duplex, simplex, upper sideband or lower sideband, frequency shift, program number, function keys to select/deselect, etc. etc. etc. ...

From Clark on Cruising World message board:
... Some words on Ham rigs. Legally they aren't type certified for transmission on marine SSB frequencies. And it is technically illegal to use one that way. Units sold in the USA are manufactured to block transmission on these frequencies. That said, every Ham rig can be opened to allow it to transmit on ALL frequencies on the bands it can operate on. If you buy it from out of the country, the dealer will likely open it for you for a small fee. ...

From Giulio Bevilacqua on the WorldCruising mailing list:
... Marine SSB should have a crystal oscillator more stable (precise) than Ham radios. At least that was the case a few years ago, now with digital frequency synthesizers that may not be the case.

From Michael Homsany:
All radios use crystals. Modern, frequency mobile radios all use a crystal as a time reference for the VFO variable frequency oscillator. They are very stable on a frequency, but the frequency displayed may not actually be the one you're on. Many ham rigs come with a 'crystal oven' option, the option maintains the crystal at a set temp to improve repeatability and also decrease drift. ...

From Rick Kennerly on the WorldCruising mailing list:
[Re: using altered ham rig on Marine SSB:]

... in foreign ports, beware. I know of one boat visiting Australia that summoned an electronics tech down to do some work. The altered ham rig was discussed and some days later the Australian equivalent of the FCC arrived to confiscate the radio. The tech also got a finders fee.

And in many countries the local government is also the local telephone company. They see HF as a way of cheating them out of money. So it pays to "turn square corners" in dealing with foreign bureaucracy. They probably won't get you, but if you somehow end up in some customs official's crosshairs, the snakes will be on you.

From Bob Austin on the IRBS live-aboard mailing list:
... I have both Ham and Marine SSB sets on my boat. Both have been modified, so I can use all frequencies (not just ham or Marine SSB). If I was purchasing a new radio I would go with the Icom 710, which has the Ham and Marine SSB, plus the distress. Stevens, SCG, and Furano also make good combination sets. Marine SSB restricts you to talk with other boats, government agencies and a limited number of shore stations. Both Ham and Marine SSB will handle data and the transmission characteristics are virtually identical. Frankly not even the FCC can tell the difference unless they are close -- unless the person using the set "illegally" does not set the frequency precisely. If I have to use my ham set on marine SSB (and to check my marine SSB set), I have an external frequency counter that reads to one Hz. FCC requires tolerance of 60 Hz. ...

The real advantage of ham is it is WORLDWIDE. There are all sorts of nets, some marine, some missionaries, some local areas, some RV etc ... Also there is FREE Email and telephone patches (non-business only). You can find a ham somewhere in the world any time day or night anywhere. I have stood a lot of night watches in the middle of an ocean talking with folks thousands of miles away. I am a medical consultant on Winlink Email (and available via Ham). I have also participated in a number of rescues at sea and elsewhere. Most military and Coast Guard large vessels and aircraft have ham frequencies available. Currently my close friend is finishing his third circumnavigation. I have talked to him virtually every day either by voice or ham E-mail during the last three years. Also via ham you make lifelong friends, who are a joy when they take you to the grocery store after you have talked to them every day as you cross the Atlantic! I still occasionally talk with people who dedicate their lives to safety at sea and cruisers voluntarily 15 years after my voyage to Europe.

Conclusion: if you are going long-distance cruising, get both Ham and Marine SSB. ...

Paraphrased from "Cruising The Easy Way" by Bill Robinson:
Marine SSB is not very useful in the Caribbean. You're usually within Marine VHF range of marine operators and other useful things. When you're not, for long distance, Ham is better than Marine SSB.

From Jim Isbell:
... the best band of all, the [Ham radio] 20 meter band. It is the one where if you really need communication anywhere in the world, you can probably get it there. I have an ICOM 725 ham rig on my boat and if I am offshore and am in a real S**t pot of trouble I will call my Mayday on 20 meters SSB and won't waste time on the Marine SSB bands. On the ham bands there are always thousands of hams listening for every signal, especially the weak ones because it might be that elusive DX they have been looking for for years. On the Marine SSB bands the owners of the rigs only turn them on when they want to join a net or when they want to talk because they don't want to waste battery power and they won't spend any time trying to figure out a weak signal. Hams have power to burn so they leave their rigs on for hours at a time and search for weak signals. Your chance of being heard is much better in that environment than in the Marine bands.

From Logan on Cruising World message board:
Marine SSB or Ham is of practically no use to you in a crunch. In the highly unlikely event you are in the **** out there, the very last thing you want is a bloody ship trying to help you. You may get moral support. You may get some useful suggestions, but your time is better spent sailing the boat so you won't need the other toy, the EPIRB.

In an actual rescue situation a waterproof (or encased) Marine VHF is your best friend. You can contact the rescue vessel and discuss things. You can use it from the liferaft. Your HF/SSB antenna will likely be down or the radio wet and inoperative. If neither is true, you should be wondering why you are getting off your boat.

From Bob on rec.boats.cruising newsgroup:
... IMHO the better choice is the Marine SSB radio for this single reason: In case of any emergency, where you are unable to operate the radio, nearly anyone can operate the Marine SSB radio, whereas the ham set is far more difficult for the average user to operate. ...

From Brian Woloshin on Cruising World message board:
Under the covers, Ham and Marine radios are very similar; the differences are the bells and whistles that Hams love. Ham radios have filters that allow you to get rid of interference that prevents you from hearing the other guy. They have speech processors that in effect increase transmit power. You need to learn how to use the various filter types (bandwidth, notch, IF shift) but once you know how you will be happier with the ham rig. The competition for technical performance and features is much greater in the Ham radio market, resulting in better, but more complex, radios.

From Rick Kennerly on the IRBS live-aboard mailing list:
HF Marine SSB and Ham use different portions of the same radio spectrum (they live in the same neighborhood but in different buildings). Most modern Ham gear will give you full coverage rx, so marine WeFax, NAVTEX, and sitor weather broadcasts will be accessible as well as the ability to monitor CG voice broadcasts. Most cruising Hams also "clip" their rigs so that they can have full tx over the entire spectrum (there are web sites that have files of directions for performing this operation). While it is illegal, except in an emergency, to transmit on Marine SSB frequencies with a Ham rig, it is not ... er, unheard of.

Your expectation of speaking to ships while underway using Marine SSB will be disappointing. Most big ships use satellite telephones to phone the home office and those that use Marine SSB operate on their private channels via sitor to home base (that's what those automated beacons are, a call sign repeated over and over again, you'll hear on Marine SSB -- a private port to connect via radio modem). Not many ships maintain a really good radio watch on the Marine frequencies any more (although you can often talk to them via marine VHF, if they are passing near). Most rely on the new semi-automated GMDSS (or whatever the acronym is) activated by the USCG or other rescue agency to notify them of emergencies at sea. So even with a straight Ham rig, you are not particularly hampered at sea.

While there are more and more Marine SSB cruising nets springing up around the world, their numbers are nothing like the number of dedicated Ham cruising nets around the world, nor is their depth of connections, service or assistance as great as those found in the Ham world. Once you get a General ham license, not only does access to the nets open up but also free Internet e-mail via radio (you've got to down-shift your expectations here, you just can't modulate an HF wave fast enough to make Internet speeds possible, so downloads are long).

But the real jewels of the Ham world are the nets. It's like a big cruising party line. You keep up with people who've gone other directions, get recommendations for SS welders in Maloolaba, weather reports (Arnold out of Raratonga in the Cook Islands used to do wonderful So Pac weather every day), and en-route check-ins (pop up with your location, course, speed and wx conditions) so that somebody will miss you if you don't come up a day or two in a row. You also get to hear other people's weather reports and can map out details of weather features that aren't showing on the charts.

So, yeah, I'd say a Ham General class license is worthwhile. Especially now that they've dropped the Morse Code requirement to 5 WPM.

From Kathy Barron on the SailNet liveaboard-list 12/2000:
> Please tell me what you know about the advantages of
> this Marine SSB "opened up" for ham as opposed to, say,
> an ICOM 706 MKIIG, which will transmit on all
> the same frequencies as the 710. I realize it
> is not "type accepted" by the FCC, but are you
> aware of any other problems?

The main disadvantage is both receiving and transmitting on the Marine SSB frequencies from a "fixed" radio. People on the other end, as well as anyone monitoring the frequency, can tell you're transmitting from a Ham radio by the quality, and you'll be able to tell the difference in signal reception and voice quality. The tuning to these frequencies, even with an SWR meter is a bit tricky. If you are a Ham operator and wish to operate on the Marine SSB frequencies (which I am and do), buy the right equipment for the job. You won't regret it.

By the way, there are two recent cases of Hams operating "fixed" radios who have been fined by the FCC.

...

Ham radios are not built with the same tolerances (as dictated by the FCC) as Marine SSB. The tolerances used for Ham and Marine SSB radios are considerably different. The standards for Marine SSB are much higher (it's in the $$). Hams radios have wider latitude for "splatter" and with a Ham radio you can use any frequency (your license allows). Marine SSB radios use preset channels which get a narrow range of frequencies into that channel. Marine SSB frequencies tune to a very fine thread which, no matter how good you are, is sometimes difficult to do with a Ham radio. The point I was trying to make about an SWR meter, and I now see wasn't too clear, is that even with precise radio and antenna tuning, to tune a Ham radio to a very precise frequency is not always easy and is very time-consuming. You have to go off the frequency to tune to it.

From "The Best Tips From Women Aboard" edited by Maria Russell (on Amazon):
... don't use a Ham radio on Marine SSB frequencies. One of our cruising friends here in Mexico recently received a not-so-nice letter from the FCC telling him that he would lose his boat's radio license if he continued to do this. ...


Idea of 2/2004 prices for Marine SSB setup:
Icom M700Pro marine SSB radio - $1100 new
Icom M710 marine SSB radio - $1400 new, $1000 used
Icom M802 marine SSB radio with DSC and Ham - $1750 new

Icom AT130 Antenna Tuner - $420 new
Pactor II Modem - $???
Cables and backstay insulators - $500

Idea of 2/2004 prices for Ham setup:
Icom ??? Ham radio - ???

Icom AT130 Antenna Tuner - $420 new
Pactor II Modem - $???
Cables and backstay insulators - $500

From Charlie Stillman on Cruising World message board:
[Talked with a couple of distributors, and:]
The Pactor list price provides relatively low margin so there's not much wiggle room for deals.

TNC vendors:
MarineNet

As of early 2005, a new protocol "Winlink SCAMP" is being tested. It uses the CPU and sound card of a PC, instead of a TNC, to do email.

Typical power consumption for Marine SSB transceiver:
transmitting at full power: 30 A at 13.6 VDC
receiving: 3 A at 13.6 VDC
[Tip from FAQs about Sarana: power consumption while receiving is important.]

Specific HF radio models:
From True Mettle on WorldCruising mailing list:
[Re: ICOM: It seems that you can only transmit on frequencies which you have programmed into a memory channel. Selecting a frequency directly by typing in its frequency on the keypad only allows you to listen on that frequency NOT to transmit on it. Anyone know of a way to modify the radio ?]

You need the program and the serial cable from ICOM. They do not release it to the general public. I brought mine into ICOM repair shop with a copy of my ham license and they modified it on the spot.

DF4OR's "ICOM CI-V Information Pages"

From Julian Frost on rec.boats.cruising newsgroup:
Don't get the Kenwood Marine radio if you want to do email ... It won't work (TKM-707) as it can't switch between transmit and receive fast enough.

From Brian Woloshin on Cruising World message board:
I have an SEA 222 and I consider it such a poor radio that I would not even sell it [to someone else]. ... Icom makes a much better radio.
Other SEA 222 owners disagree. One says that SEA says the 222 is not suitable for email use and they have a newer model intended for email use.

From John / Truelove on The Live-Aboard List:
I have the SEA 235R and love it. Get the 1635 coupler, too. It's a great coupler, but it can have problems tuning on 4 MHz if you have a certain antenna length. Talk to SEA about what antenna length to use before you install the coupler. Do not whistle the mic to tune - hit the tune button.

From Will on Cruising World message board:
The SGC 230 antenna tuner is the best of the lot in terms of overall antenna efficiency. In some cases the field strength readings is as much as 50% greater on the same backstay length than the Icom AT130.

From Will on Cruising World message board:
I use a SGC Marine SSB, and the main reason I selected it was that it had a free tuning VFO which for a Ham and any serious radio op is a must. Up/down buttons just don't cut it. The channel programming system on the Icom is awkward. The most overlooked reason for selecting the SGC, is that it can operate at very low battery voltage before its circuits become unstable. It operates down as low as 10.8 volts before it starts to distort. Most ham radios and Icoms must have 13.8 volts +- 10%; anything lower they start FMing and sound more quacky than Donald Duck on Drugs. I had a very early version of the Icom 710 and had numerous problems with that particular radio; the problems were widely known. I sold this radio along with my boat. The Icom 710 is just a Ham radio in a different box; quality of wire connections in this radio is poor. The SGC is vastly superior in aspects of construction and materials. The receiver is also much better, it has a high ability to withstand multiple strong signals on bands like 6 MHz and 8 MHz in Asia, where an Icom will start to generate spurious image products. The best thing about the Icom is the price. The advantage of carrying Icom is that service is available anywhere in the world, although I had problems with Icom Australia who did not want to know about my problems because I bought the unit in Asia for 1/3 of the price, but this is typical of Australian service when it comes to international brands.

From Steve on Cruising World message board:
We have used a SGC and Smart tuner on our boat for the last 5 years with many problems. First the tuner would not work, come to find out a capacitor was installed at assembly reverse polarity and burnt out. We had it fixed in Mex. SGC paid the bill. Then T/R relay went out, they fixed at a way $ fee. Now the T/R relay is giving us problems also we are having wide frequency splatter when sending Ham PACTOR E mail. Checked all installation tricks, set TNC output with a scope etc. Contacted SGC, they will look at it for a flat fee of some $400 or so.

Lots of problems with other SGC radios in the West Coast of Mex. fleet. Sooo, if you are planning on a new radio, talk to people who are out there using them.

From True Mettle on WorldCruising mailing list:
I own two SGC-2000 ADSP models with tuners. Both of them have been "road tested". By that, I mean that there are two types of SGC radios, ones that have been to Seattle for repair and ones that are about to go to Seattle for repair. When the radio works, it is incredible, but it does do weird things at the wrong times. I was off the coast of Mexico and tried to send a message when the radio refused to transmit. I got to port and could not replicate the problem. I brought it back to Seattle and they heated, cooled, beat, shook and generally tested the radio only to report to me that there was nothing wrong with it. I am a RF engineer and I can tell you that the radio really did have a problem!

The tuners on the other hand are the best in the world. Have a close look at any American naval vessel and you will see an SGC-230 tuner painted in military colors and worth 1000 times the cost of the retail version of the same unit hanging under any of the Marine SSB antennas. It will literally tune a wet piece of string. I like the tuner over the Icom as it can be used with ANY radio; the Icom needs Icom band signaling from the radio.
From John / Truelove on WorldCruising mailing list:
I had a new SGC-2000 for 9 months. It went back to the factory 4 times before they replaced it with a new one. That was facacta as well. I made very loud noises at SGC and got a full refund thru the dealer, from whom I then bought an SEA 235R.

I have heard the same comments as True Mettle: *if* you get one that works, it's the best around. Problem is, it's 60's technology; there's just too much hardware in the thing.

Also agree about the tuner, altho' the SEA tuner tunes just fine.

From Felix U on SSCA discussion boards:
The SGC 2020 is a reduced-output radio, that probably wouldn't provide enough power for reliable communications from a boat. I spoke personally to a well-known radio reviewer who described it as "a piece of crap". There is an SCG 2020 users group, and they are a Greek chorus of complaints about the shabby reliability of this unit.

Lots of problems with SGC radios, from lots of owners, mentioned in article by Jeff Williams in Jan 2002 issue of Blue Water Sailing magazine.

From Mitch on The Live-Aboard List:
We recently installed an Icom M700 Pro and it has been fantastic both for voice communication and for e-mail through a PTC-IIe TNC. We tried the SGC 2000 with the powerhead and it had problems so went with the Icom. I highly recommend it. The ground was no problem - just ran copper foil, although the Nic 32 has a bit of steel in the hull aft so I also use that. There really wasn't much wrestling. We connect it to an SGC-230 Smart Tuner - which I am also very happy with. People I communicate with indicate that I have a very good signal.

I do know of several people using the SGC 2000 successfully. The SGC has a slightly better tolerance for low voltage.

From Will on Cruising World message board:
If you are looking to buy THE BEST HF RADIO in the world, look at Mobat. You can also find info on the Motorola USA site. I have been using the Micom now for 1 year and I am really impressed. The radio is sold by Motorola in the USA. There is not a single HF/marine radio that is as good as the Micom.

From Rick Kennerly on The Live-Aboard List:
[Re: What ham radio to get:]

...

About the finest radio there is is the TenTec. Unfortunately, it's an abysmal radio to cruise with, unless you never leave the states.

Yaesu is about the worst HF ham rig made.

Alinco's are relatively new to HF and I really don't have any good info on them.

Also, stay away from SGC and SEA radios -- not because they're bad radios but because of the proprietary interface which means you have to buy all their high-priced add-on items, like a TNC. OTOH, SGC makes a great external antenna tuner that will interface with any rig, as does ICOM. I've got the SGC tuner aboard our boat.

Personally, I'd shop for either ICOM or Kenwood. I've been running an older Kenwood TS 440 AT that I got used for several years now and it's been fine (it's been modified to transmit all-band, including Marine SSB -- just in case of emergency, of course). If you're buying new, the newer smaller units (about the size of a car radio), like the Kenwood TS 50 or the ICOM 706, have all the features you'll need and have standard interfaces. Stay away from the really high-end rigs. They're great for base stations and DX competition, but they're way more radio than you need for MM work.

You can get the dual service (Marine SSB and Amateur SSB) 710, but you should be aware that while it's a great Marine SSB, it is a clunky Ham rig interface. OTOH, since you've not experienced working a good ham rig, you might not miss having the controls to tweedle with.

...
From Jim McCorison on The Live-Aboard List:
> Also, stay away from ... SEA radios --

The heck with the proprietary interface. Stay away from SEA because they're going belly up. In mid-November [2001] they laid off most of the staff, and are either not manufacturing any product or severely curtailed manufacturing, depending on who you ask. As of 1/2002 no statement about when or if they'll ever start shipping product normally has been made.

From article by Jim Corenman in 10/2001 issue of Latitude 38 magazine:
Get Icom M710 or 710RT for email.
Next best would be SEA-235 with optional fan.
Don't get SGC SG-2000, which has a variety of problems.

From Susan Meckley on World-Cruising mailing list 11/2007:
I myself have used (for 6 years) and have installed many SSB rigs for cruisers.

BY FAR, the least expensive way to go is the ICOM 718. It has everything you as a new ham or even some experienced hams would want ... even plug-and-play EMAIL.

For the email you need a TNC (Modem). If you can find a used PACTOR IIe, get it. Send it to Farallon Electronics in Sausilito, CA for updating.

For an antenna tuner there is only once choice (in my opinion): The SGC 239. It will handle up to 250 watts, is not "RIG" dependent like ICOM, Kenwood, Yaesu, etc. It will work great with any radio. If you change radios, you are not stuck with having to buy the same brand as your antenna tuner. SGC does MIL-SPEC equipment. The SGC239 is only $182 and does not have a waterproof case. So SGC recommends you put the unit in a "Tupperware" type case ... VOILA ... waterproof.

DO NOT CUT YOUR BACKSTAY for an antenna ... to do so is to create another failure point. Instead just run a wire from an insulator back aft up to the top of your mast. Make sure it is out of the way of the mainsail.

For a ground, run strips of copper foil along the "tumblehome" of the bilges ... go to a stained glass supply/hobby store. They sell 3/4" foil at about $9 for 40 yards. Run three strips on each side of the tumblehome ... they are sticky-backed. Solder them together ... even run a couple of strips up to the transceiver for a ground.

From Susan Meckley on World-Cruising mailing list:
If anyone does buy the sangean 909 from c crane co: Ask them to do the modification so that the audio does not blank out between dial positions. I did, and I really like it.


From Don Melcher of H.F. Radio On Board:

Digital Selective Calling (DSC):
From Don Melcher of H.F. Radio On Board:
Digital Selective Calling (DSC) is available for Marine VHF everywhere and Marine SSB outside USA (but not for Ham radio), and worth the small extra cost. It allows your friends to "make a phone call" to your radio from their radio. Your radio will "ring", and tune to the channel they're on, regardless of what channel your radio was on at the time.

USCG's "Digital Selective Calling"
BoatU.S.'s "MMSI"
VHF DSC article by Ben Ellison in 5/2004 issue of Sail magazine

You can get an MMSI unique ID number (identifying code for new DSC-equipped Marine VHF radios) from several companies (BoatU.S., Sea Tow, Standard Horizon) without paying the Feds $200 (or is it $160 now ?) for a ship's station license. But an MMSI obtained that way is valid only for recreational vessels in USA waters. For a valid international MMSI (if issued by USA, ends with "0"), you must get the Ship's Radio Station license ($200).

From article by Darrell Nicholson in 12/2002 issue of Cruising World magazine:

My understanding of using a USA-only MMSI on marine VHF while outside the USA:

Question I asked 9/2011:
If there is no MMSI number programmed into a Marine VHF radio, will it still send a DSC distress call if the user presses the red button (or whatever operation is needed for that particular radio) ?
Answer from Cobra Electronics: yes.
Answer from Standard Horizon: no.

I bought a Cobra MR F45-D marine VHF radio with class-D DSC 11/2011:

From Jim on rec.boats newsgroup:
... You will lose about 60% of your range on a DSC call and another 20% on a scrambled call, but you can always use it like any other Marine VHF and get full range. ...
Response from Don Melcher of H.F. Radio On Board:
Well - I think that is a pretty drastic statement - and one I can only answer drawing on practical experience with ham radio. DSC is a digital data burst and has to be received correctly in order to be decoded - with voice, the human ear can make up for errors that digital cannot ... but I think that is an invalid statement and is something that is difficult to quantify - DSC is similar to packet radio used on ham radio and packet radio was used quite successfully to communicate with MIR and the space shuttle ... I hazard a guess that worst case is that DSC would have about 80 - 90% of the range. Scrambling is another but similar issue, and there are various scrambling techniques - the ones employed in Marine VHF are pretty rudimentary, and probably have a degradation of 25% or more in range ... but again, it would be hard to determine without doing some extensive laboratory experiments. But to address your question - I find it VERY difficult to believe that a Marine VHF signal that has a usable voice path of let's say for the sake of argument 50 miles, that the DSC range would only be 20 miles and 16 miles on scrambling - that certainly HASN'T been my experience with VHF Ham Radio packet radio - I have found very little difference in the useable range.
Manual for my Cobra DSC VHF radio says range for digital (channel 70) part of DSC call may be longer than range for a voice call, or voice part of a DSC call. So the digital part of a normal or distress call may go through, but then you might not be able to establish the voice connection.

Cell-phone versus radio:
Cell-phone is worse: Cell-phone is better:

Choosing a Marine VHF radio:
Want: For handheld, also want:
Common problem for handheld VHF: if it gets wet and is left wet, the battery pack is destroyed and the battery connectors are corroded. Since a new battery pack is more than 50% of the total cost of the radio, this is a disaster. After every use, before you put it away, take the battery pack off and store it next to the radio; this will force you to see if it is wet.

From Ron Rogers on The Live-Aboard List:
A review of "Practical Sailor" would reveal that VHF performance data varies significantly from manufacturer's claims. A high-quality antenna, installed properly, makes a huge difference. So does the actual voltage reaching the radio under load - when transmitting. Some high-quality radios are far more tolerant of low voltage than others. Lastly, some VHF's cannot transmit for a sustained period of time. This is a system, not merely transceiver, selection and purchase.

From Pilgrim on The Live-Aboard List 2/2005:
... Watch out for problems with the ICOM 402 REMOTE MIC. Mine has been in for service twice a year for the last 3 years. I use a remote speaker off the main unit and only use the remote to change channels. Since the remote mic seems to love opening up the squelch at random it is useless. ...


Marine VHF antennna:
"Open" versus "shorted" antennae:
There are two "types" of marine VHF antenna: An "open" type of antenna is better. With a "shorted" antenna, when using a multi-meter from the cockpit, you can't tell the difference between a good cable and antenna, and a cable that has shorted to itself somewhere along its length. And a shorted cable can kill your radio.

On the other hand, with an "open" antenna, when using a multi-meter from the cockpit, you can't tell the difference between a good cable and antenna, and a cable that has broken (opened) somewhere along its length. But this failure won't kill your radio.

I'm told:

From Ed Russell at GAM Electronics Inc:
52 ohms is the resistance found in most marine-grade coaxial cable and is what we use as cable for testing and tuning our antennas. Thus they are "matched" to 52 ohm cable at peak resonance.

From Gary Detherage:
Most antennas have a base load coil that measures very low DC ohms but the RF impedance is 50 ohms.

I'm told: using a VHF radio with a cable or antenna that has shorted across the two sides of the coax will blow out the radio as soon as it is powered up, or as soon as you transmit.

From Tim Factor at Standard Horizon / Yaesu 9/2011:
Yes, you can burn out your final transistors if you attempt to transmit with a shorted antenna cable.

From Brian Burke at Cobra Electronics 9/2011:
If the antenna is shorted then it will not be good for the transmitter. It won't blow instantly, but it can fail after numerous transmits. It depends on how long you hold the transmit button.

If you don't transmit, then a shorted antenna will not hurt the radio. It's only a problem if you transmit.

I recommend that you turn on the radio and see how well it receives. If receiving appears to be working well then the antenna probably is fine. The only way to check further would be to check the SWR with an SWR meter.

My suggestion: It woud be great if manufacturers would build a feature into future radio models, to test for a cable short at power-on, to avoid damage to the radio.

From Catalina Fleet 21's "Marine VHF Radio FAQ Page":
A basic rule of thumb is: the higher the antenna, the better the reception. VHF signals are line-of-sight only. So, the higher your antenna is mounted, the farther it can "see" to the horizon. ...

Gain is an increase (or decrease) in "effective radiated power" from an antenna, usually stated in plus (+) or minus (-) dB (decibels). VHF antennas come in gain categories, like 3 dB, 9 dB, etc, which are a measure of how efficiently the antenna deals with the signal it is fed from the radio. Gain depends greatly on antenna length. Generally speaking, you can add four times the radio's output power for 6 dB antennas and 8 times the radio's output power for 9 dB antennas.

Antennas with a high dB rating concentrate signal energy perpendicular to the antenna shaft in a relatively flat wave form. This provides a more concentrated signal, but can also cause fading as the boat pitches and rolls. ...

Shorter antennas are rated at 3 dB and transmit energy in a less concentrated and broader pattern. This makes 3 dB antennas ideal for sailboats, since the less concentrated signal works better when the boat and antenna are heeled fron vertical. Mounting a 3 dB antenna at the top of a sailboat's mast will usually compensate for its nominally shorter range than a higher dB rated unit. A short antenna mounted atop a sailboat's mast can give performance equal to or better than a long antenna on a small boat.

From Catalina Fleet 21's "Marine VHF Radio FAQ Page":
For a quick test to see if the connector and antenna are working properly, tune in a weather channel, then disconnect the coax from the radio - making the signal become weaker or disappear entirely. Put just the center conductor of the PL-259 connector in the radio's connector. The signal should return but with poor fidelity and strength. Finally reattach the connector. The signal should return to normal. If instead, it goes away completely, there is a short circuit at the connector or in the antenna coax.

From donradcliffe on Cruisers Forum:
To test the cable, you need a helper at the top of the mast.

Step A: with the cable disconnected on both ends, check the resistance between the shield and the inside wire (the shell and the pin of the PL259 connector). It should be at least 1 megohm.

Step B: have the helper short between the pin and the shell of the connector on the top of the mast, and again measure the resistance between the pin and the shell at the radio end. It should read less than 5 ohm.

From Jim Genius 11/2011:
Testing your antenna with a DC ohmmeter does not work. DC current and RF (radio frequency) current are two different things. A DC short can be a perfect RF load.

What is usually used to test antenna and cable configurations is a standing wave meter. This gives you the ratio of the power out of the transmitter to the power reflected back to the radio (the energy not transmitted into space by the antenna). Almost all modern radios will reduce power at high standing wave ratios to keep from damaging the radio. Most VHF antennas are a 5/8 wave length (speed of light divided by transmitting frequency) feed by a loading coil (DC short) to give a 50 ohm impedance (not DC load) at the transmitting frequency.

Testing Cable with a DC ohmmeter can give you a headache! A length of cable has both capacitance and inductance. When you use an ohmmeter to test the cable, the small DC current will first have to charge the capacitive and inductive reactance of the length of the cable. This is a small value and stabilizes after a few seconds. The main problem is getting a good DC connection on old corroded fittings.

The best way to test your VHF installation is to borrow or buy a VHF SWR meter (starting at about $25). SWR should be below 3 to 1.

From Catalina Fleet 21's "Marine VHF Radio FAQ Page":
Marine VHF requires 50-52 ohms impedance coax, so don't try using cheap TV 72 ohm coax or CB coax. It is a good practice to check the coax with an ohm meter before installing connectors. After installation, check again for the same reading.

From Ken on "Silverheels 3":
Marine VHF antenna cable degrades over time in sunlight; chemicals from outer sheath migrate into the dielectric and degrade it. Use thick cable (RG-8) instead of thin (RG-58, RG-59).

On exposed connectors at the top of the mast, don't use electrical tape over them (that just seals moisture in). Smear "coax putty" over the outside of the connectors to seal them completely.


From Adam Chorley:
I'm an electronics technician, and have noticed people bringing me their Marine VHF radios with WD-40 inside the case - obviously trying to stem the corrosion issue. This is a big no-no. What I have done with all my electronics (including those I service for marine use) is apply a coating of MILSPEC "conformal coating" to the PC board (both sides) after using silicon [silicone ?] to glue all parts that are susceptible to movement/vibration. I did this with a portable Marine VHF radio (non-weatherproof) I have had on 3 different boats for over eight years - it is still as good as new. You can source this stuff from any electronics store, but I would recommend application only by qualified people.

On-line radio stores:
Ham Radio Outlet

Satellite Radio:
Most of the satellite receivers sold are not complete radios themselves; instead they receive the digital signal and rebroadcast it on FM to whatever standard FM radio you have.

Services:
Sirius
WorldSpace (maybe a subset of XM now ?)
XM Satellite Radio

Details:

From Derek Rowell on Cruising World message board:
XM:

I have the Delphi Sky-Fi system and use a "home" adapter with the FM modulator to couple to the stereo. We carry the receiver to and from the boat and use it constantly at home also. I installed a Terk XM-5 marine antenna on the pushpit to get omni-directional reception because the Delphi antenna is fairly directional.

The only problem is that the receiver seems to drop-out and turn itself off when the battery voltage falls below about 11.7 volts. I've just purchased a cheapy ($29) 12v - 12v dc-dc regulated converter to take care of that and will install it in the spring.

Thoroughly recommended!

From Imagine on Cruising World message board:
Sirius is recommended for cruisers who plan to go to the Caribbean or South America. As I understand it, there are three Sirius sats in an elliptical orbit covering North and South America, while the XM sats are geosynchronous over North America only.

I have a Sirius for my boat and love it. I bought an additional docking station and can move the radio between car and boat.

From Woody on SSCA discussion boards:
The XM sats are geostationary and have focused antennas. As a result they are limited to the continental US with some stray signal to Canada and Mexico. I have read reports of success in Bermuda, but it seems the signal dies south of the Bahamas.

Sirius, on the other hand, has three sats that orbit in a figure eight over south and north america. At least two are over the US at all times. Because they are moving, the antennas are not as focused in order to maintain a large coverage area. It looks like they are turned off only as they move south of the equator. The result is a much wider coverage area outside of north america. I have read of good signal reports from most of Mexico, Bermuda, Bahamas, Puerto Rico, Panama, and even Hawaii! I have not read of any reports good or bad from the windwards. Going North there is good coverage well into Canada and Alaska.

From Jack Tyler on SSCA discussion boards:
There is a different system being used in the Med and N Europe, coming off two Euro satellites. XM and Sirius are intended for North American audiences.

From Patrick on SSCA discussion boards:
I live in Nevis and just got Sirius up and running last week. I usually experience outages late at night, but works great during the day. It appears that the satellite must be lower on the horizon at that time because I can always find the signal by adjusting the antenna.

From David on "Encore":
The weather broadcasts on XM give local forecasts for major US cities, not marine/offshore forecasts.

I was told that Sirius worked fine in Luperon DR.

Someone in St Croix told me that using Sirius (not sure where) required moving the antenna to keep it pointing at a satellite when the boat swung at anchor.

From Bongo on Latitudes and Attitudes Cruisers Forum 3/2006:
I can verify that XM does not reach as far as BVI. Tried it.

I would think hard about the lifetime subscription thing. Both XM and Sirius have reported significant losses and are spending money like a drunk sailor on shore leave. I'd recommend staying short until they stabilize their finances.

My experience with Sirius:







Phone On Boat


"I have always wished for my computer to be as easy to use as my telephone.
My wish has come true, because I can no longer figure out how to use my telephone."
- Bjarne Stroustrup (en.wikipedia.org)

Inmarsat-C GMDSS:
From Dave Richardson on the WorldCruising mailing list, 3/2000:
... Inmarsat-C is IMHO the most reliable, lowest cost, satellite based data transmission system available today. If you can afford it Inmarsat-M provides voice but is not attractive for data. If you are looking at satellite voice then KVH makes the nicest system for about $10,000 with voice at something like $8 per minute. This is the system gold-platers go with where cost is no object. Inmarsat-C is part of the global GMDSS effort and as such you receive free transmissions on regional weather information, search and rescue, gale warnings etc. Trimble makes an integrated Inmarsat-C transceiver with GPS built in. It is about $2900 and transmissions are about $2 per minute. ... By the way you will need a Maritime Mobile Service Identity (MMSI) issued by the flag registry country to activate the system. ...

Marine SSB radio to long-distance phone system through WLO ($4 - $5 per minute).

From John / Truelove on WorldCruising mailing list, 9/2001:
Looks like Iridium is here to stay. Globalstar's financial position does not look promising, so I crossed them off the list, despite their 9600 baud data; Iridium is half that, but promises 10K, using compression, soon.

An "old technology" Kyocera phone and marine antenna can be had for $900, but it isn't data-ready. The "big" (original Iridium) Motorola phone is $895 new or $495 refurbished. That's what most folks buy. The new, small Motorola phone is $1495, but is waterproof, digital-ready and hands-free capable, yada, yada, yada.

The best provider rates I could find were $1.40/minute, which I find reasonable for "any time, anywhere" phone and data service. Due to competition, rates are falling, albeit slowly. You can call another Iridium phone for $0.85/minute. The monthly charge is a flat $20.

The slick way to go is with the 9505 (small) phone, the portable dock, and external antenna. This rig will cost $2795. The data software CD is $65 (ouch!). The phone comes with a charger, so all you need for down-below 'phone service is the outdoor antenna, which can be directly connected without the docking station (they don't say that in the ads). There are also less expensive antennas than the standard one. ...

From Don R on "Windaway":
Even a de-activated cell-phone is legally required to allow calls to 911; get a discarded cell-phone and keep it aboard as an emergency device.

From Gordon West in 11/2005 issue of Sail magazine:
To maximize cell-phone range, get a wireless amplifier such as those from Shakespeare or Digital Antenna, and a rail-mounted white-fiberglass high-gain cell antenna system.

VHF-phone-patch (and more) service: Sea Smart.

From Judy Rouse on World-Cruising mailing list 8/2006:
Cellphones outside the US are incredibly cheap and most do not require any form of contract -- it seems to be a foreign concept every place we have visited since leaving the US. Here in Trinidad we purchased a Motorola C139 for 10USD -- no contract, no prepaid penalty, no minimum, no nothing. We purchase minutes as needed. It costs 20 cents per minute (USD) for daytime minutes, 16 cents per minute for nighttime minutes, and 8 cents per minute for weekend calls -- for outgoing calls only, whether local or international. ALL INCOMING CALLS ARE FREE!!!!

This same Motorola C139 can be purchased at another local cell provider for only 8USD. Only problem with these phones are that they are only dual-band GSM and are locked, so they cannot be used elsewhere. But at this price they are disposable. From what we have seen during our trek so far, it is cheaper in the Caribbean islands to purchase local cheap phones than to have a more expensive quad-band GSM phone, because of the cost to purchase minutes locally for the foreign phones. Every island has had similiar ultra-cheap phone deals.

Appears that only in the US do we pay exorbitant phone charges.

...

... We call relatives and friends back in the States and tell them to call us back -- takes less than 30 seconds. They then call us back using Skype because they all have broadband internet connections ...

From Judy Rouse on World-Cruising mailing list 8/2006:
Verizon has a policy whereby if you move to a location where Verizon does not provide service, then they will terminate your cellphone contract early without penalty. Verizon requests proof that you are indeed moving to such a location. They want something like a mortgage, a drivers license in the new area, or a letter from your employer, etc.

We had Verizon service in Texas. When we left at end of April, we had employer fax a letter to Verizon accounting department contact person which stated that we were moving aboard our sailboat which was located in the BVI (where Verizon does not provide service). It still took about 6 weeks and 3 additional follow-ups on our part to finally get the service terminated.

For coastal cruising, many cruisers are using Skype to telephone. You need a computer, headset and internet connection. Skype-to-Skype calls are free. Skype-to-phone calls cost 2 cents/minute in USA-type places, higher in remote places (but still cheap). And you can't receive incoming calls if you're not booted up and connected (but they sell voice-mail and other services).

Can buy a "Skype phone": it looks like a cell-phone, but it's really a Wi-Fi phone with Skype embedded in it as the operating system. Some vendors: Belkin, Netgear.




Getting Started in Ham Radio


[I believe as of 1/1/2007, there is no longer any Morse code requirement for any license. Not positive.]

To get started in Ham radio:
  1. Read How Stuff Works' "How Ham Radio Works".


  2. Read an overview book, such as "All About Ham Radio" by Harry Helms (on Amazon).
    This gives a good overview of what Ham radio is, what the licenses are, some of the technical material, etc.


  3. Read a study guide, such as "Now You're Talking" by ARRL (on Amazon).
    This is a study guide for the Novice and code-free Technician's tests.
    Reading and studying this takes about a month.

    Get a fairly recent study guide; I used an 8-year-old guide and 20% of the questions on the test were unfamiliar.

    My opinion: don't bother to learn Morse code yet; start with the code-free Technician's test. And don't bother to memorize trivia such as the frequency bands, Qxx codes, power limits; you only have to get 74% to pass the test.

    AA9PW Amateur Exam practice pages


  4. Go to ARRL's "Licensing, Education & Training" to find an examination session in your area.


  5. Schedule and take the test.

    Costs about $6.

    The examination people will help you file the FCC paperwork afterwards.


  6. Receive your license in the mail from the FCC. (My call-sign arrived in email 11 days after the test.)


  7. If you want to do email (digital) over HF, you need a General class license.

    This requires another study guide (for element 3B), and also passing a 5 WPM (but dashes and dots at 15-18 WPM) Morse code test.

    Most of the element 3B questions are identical to the Technician's questions; take the 3B exam ASAP after the Technician's exam.


  8. Morse code:
    • I found it easiest to learn Morse code by memorizing a pattern-based order instead of an alphabetical order.


    • Very important: choose a VEC that gives an easier test (probably a boat-oriented VEC as opposed to an old-time Ham VEC).
      From one VEC: "Listen to 5 minutes of audiotape; text is a ham radio QSO. We do not permit writing down dots and dashes. Repeat do not. Ten multi-choice questions; must get seven correct. Then examiner reads your copy seeking 25 correct characters in a row.".
      Some VECs require some sending in the 5 WPM test, too.
      Another VEC does allow copying down dots and dashes.


    • Ask what subset of Morse code the VEC tests.
      There is international Morse code, but then also "procedural signals".
      From Don Melcher of H.F. Radio On Board:
      The requirements for the morse code test should be covered in your license manuals and is part of what you are supposed to be familiar with for passing the current element 3 written test. The characters we are REQUIRED to test you on are part of the FCC rules - basically the 26 letters of the alphabet, numerals 0 - 9, punctuation .?, /, and the "prosigns" for end of message, break, and end of work.

      Our format is a plain text message, something along the lines of "This is the amateur radio morse code exam at 5 words per minute. The 6 quick brown foxes jumped over the 3 lazy boys back 7 times." Followed by whatever characters we haven't used, sent in a random groups of 4 to 5 each. You are required to copy 25 characters in a row correctly - numbers and puncuation count as two characters. You must also demonstrate an effort to copy the entire message. We use the Farnsworth method - the code is at 5 words per minute but the characters are at 15 words per minute.

      ... You need to bring the original and a LEGIBLE copy of your current license, the original and a LEGIBLE copy of your CSCE showing you passed element 3B, a photo ID and $10 cash.
      From Emmett Freitas (runs a VEC):
      So far as I know no VEC in the country uses anything other than Farnsworth. You have no choice in that wherever you go.

      The variant is the character length. The ARRL/VEC character rate now is about 18 WPM with the spacing set so the information imparting is at the rate of 5 WPM. This means that seventy percent of the code tests in the country are to that standard. The remainder of the VEC's are within a hair of the 18 WPM character length.

      Some time in the future the character length will drop to about fourteen WPM. Probably about April [2001]. This standard will be used everywhere. ...

    • Find software such as Stormy Weather SoftWare's Morse Code Training Program or Super Morse (move to empty directory before self-extracting, wants short directory name like C:\SM, complex) or Ward Cunningham's morse.exe (fairly simple; press Enter to get menu) or MorseQuiz by AE4RV (just quiz, no teaching) or Koch CW Trainer, or Just Learn Morse Code, or Morse Academy.



  9. Buy a receiver or transceiver.

    Want:
    • Multi-mode (FM, SSB, CW).
    • Multi-band (20-meter, 50-54 MHz 6-meter, 144-148 MHz 2-meter, 156-158 MHz marine VHF, 162 MHz weather).
    • High selectivity (aka "low bandwidth").
    • Easy-to-use frequency display and controls.
    • Signal strength meter (aka S meter).
    • SWR meter (aka reflectometer).
    • DTMF-sending.
    • To use for email:
      • Must tolerate high duty-cycle,
      • Must have decent on-frequency control,
      • Must be able to connect to modem,
      • Must have fast TR-switch time,
      • Want ability to transmit at reduced power.

    Since I want to hear Caribbean signals from California, I probably want a table-top model with ability to attach external antenna.


  10. Use it in receive-only mode for a while to get a handle on things.



A mega-site: AC6V's Amateur Radio and DX Reference Guide
CompuServe's HamNet Forum (also has a library of downloadable files)





Ham Radio Operation


Mostly from "Now You're Talking" by ARRL (on Amazon):
BandBehavior
10 meter (28 MHz)Best during high sunspot periods.
15 meter (21 MHz)Good for long distance.
20 meter (14 MHz)"It's the closest to an all time, all places, band. [But still subject to atmospheric variation.]"
40 meter (7 MHz)Lots of shortwave broadcast interference.
400-1200 mile range in morning and early afternoon.
Several thousand mile range in late afternoon, evening, night.
80 meter (3.7 MHz)350 mile range in daylight.
1000 mile range in summer nighttime.
Several thousand mile range in winter nighttime.
VHF/UHF100 mile range in winter.
Up to 1000 mile range in spring/summer/fall.

Tune in the time signals (WWV on 2500, 5000, 10000, 15000, 20000 KHz, or Canadian on 3330, 7335, 14670 KHz) to figure out propagation on different bands at various times.

SailNet - Jim Sexton's "Marine Radios Overview - Side Bar"

A marina is a really bad place for radio use: there is lots of electrical noise (from engines, inverters, shore power, radios), and the rigging of other boats can act like [unwanted] antenna elements.

From John / Truelove on World-Cruising mailing list 11/2002:
With all due respect to Rick, the wonderful experiences he had with Ham radio in the Pacific many years ago differs considerably from those experienced by me and many of my cruising friends. There weren't nearly as many cruisers back then, nor were the airwaves as jammed with traffic. Now, in the North Atlantic and Caribbean, Central and South American illegals regularly transmit on LSB, just close enough to QRM many marine channels, making them unusable. Cruisers who are not Hams don't have as many frequencies to choose from, and the proliferation of cruisers attempting to send data via Sailmail and the like have, in close quarters, made even Marine VHF comms difficult in crowded anchorages.

Chaguaramas, Trinidad is an infamous radio "black hole," not only because of the terrain and interference from land-based power lines, but because oil rigs, 600 sailboat masts and a 3-acre steel roof, all in 1/2 a square mile don't make for good radio! As if that weren't bad enough, over the past five years that I've been in the Caribbean, the sunspot cycle has been at peak, making Marine SSB comms a problem everywhere. Good luck talking to the States, at least reliably! And anyone who listens to Herb knows that transmission/reception over this same period has been close to impossible for many boats in the Atlantic basin.

I've tired of attempting to raise (or hear) another boat in the Eastern Caribbean. Too many times you just can't. And as anyone who has buddy-boated on passage knows, there is often a big gap between the Marine VHF's maximum and Marine SSB's minimum. But who doesn't answer the 'phone? To say nothing of the privacy afforded.

As regards Ham wx (and other) nets, they're the best, for sure. But when you can't hear them they are useless. Using Marine SSB to access WEFAX, NAVTEX and the CG and Navy wx forecasts is like night and day compared to accessing the same data (and more, such as Gulf Stream info) on the Web via satellite-based systems.





Weatherfax (weather-fax, radiofax)

SailNet - Jim Sexton's "Weather Fax"
SailNet - Michael Carr's "Weather Information Sources"
SailNet - Michael Carr's "Reading Weather Fax Charts"
NOAA's "Marine Radiofax charts"

What it is:
SailNet - Michael Carr's "Surface Weather Overview"

How to receive it:
You can get a dedicated weatherfax receive-and-print device from Furuno ($1500). Apparently you can use normal thermal fax paper in it if you peel off a third of the roll first (takes 66-foot roll instead of 100-foot roll).

If you have an internet connection: NWS Marine Charts.

Most people seem to be getting weather maps through email instead of weatherfax. Probably a lot more reliable, and you don't have to listen on a schedule.

Software for receiving via radio:
Weatherfax software tested in 5/1/2001 issue of Practical Sailor (JVComm32 rated best buy).
HF-Fax's Software page

From Justin on Cruising World message board:
My parents have 3-month-old Coretex software and I have 3-year-old HF/Fax software. Personally I think my software is much better even though it's older. I would imagine the newer version of HF/Fax is even better.

There were a couple of features for editing, viewing the transmission frequency, and printing that I thought were better than the Coretex.
From Dennis / True Mettle on the WorldCruising mailing list:
I don't know much about the radios (I have a Marine SSB) but I have owned all kinds of WeatherFAX demodulators. At the most expensive end is the SCS Pactor-II and the JVcomm program (SCS). The faxes were ok, but the solution is expensive. The next in the list is the John Hoot SSCorp fax demodulator. His software gives you quite a bit of flexibility albeit some of the faxes themselves are unreadable. It's in the $175 price range. (SSC Corp) Another good offering with the demodulator concept is Xaxero and it's about in the same range pricewise (Xaxero Software). After spending all this money I found that the JVcomm software ~$80 connected directly to the speaker output of my radio to the microphone input of my laptop works the best (HF-Fax or JVComm32 Homepage). The German website is probably the most comprehensive one out there.


From Larry DeMers on the IRBS live-aboard mailing list:
Really, any good HF General Coverage Receiver with SSB capability (has the ability to tune either USB and LSB true to within 1 KHz) is able to provide a Weatherfax signal to the demodulator via a small set of wires attached to the speaker output. There are several packages of software and software with hardware that then take the signal and process it for display.

Weatherfax is **very slooowww** coming across. One single chart of the Pacific will take the best part of a half hour to accumulate on screen. I believe that it comes in at 300 baud (the old TTY speeds). It also helps to have a good long-wire antenna deployed onboard, rather than the included whip antenna ... although that will work also. Realize that any noise picked up by the receiver will appear as a black line in your screen picture. If there are thunderstorms between you and the xmtr., you will hear these crashes of noise, as well as see them as black lines on the weatherfax. There are more expensive ways to receive the actual satellite signal onboard, and then print this to a printer along with the geographical overlay for that area. These satellite receivers are a lot faster and cleaner, with much better resolution.

From Justin on Cruising World message board:
We have the Grundig Yachtboy 400. I believe it was about $199 when we bought it 2 years ago. The weatherfax software comes with a demodulator and cable that connects the radio to the computer (headphone jack on the radio to a serial port on the computer I believe).

When you have the headphone jack plugged in on the radio you lose audio from the main speaker. This makes it really tough to tune the radio to the exact frequency since you can't hear what is being received. So at Radio Shack you buy a headphone jack Y-adapter. Now you can connect to the PC and to headphones at the same time, listen to the radio and tune the frequency. Also, if you were offshore this keeps you from disturbing the off-watch with that annoying weatherfax - gong, gong, click, click, etc ...

The Si-Tex does the same except it is not a portable radio - requires a 12V source. The Grundig is AM/FM, shortwave, alarm clock, and portable.

We use HF Fax software. Ours is 2.5 years old and a DOS version. It is works fine, but I suspect the newer Windows version would be preferable.

From Will on Cruising World message board (not about weatherfax):
The only disadvantage of the Yachtboy is that it does not have upper and lower sideband selection [Yachtboy 400PE has switch for turning "SSB" on or off; have to change freq to move between LSB, carrier, and USB]. A better choice would be the Sangean ATS909 or the Radio Shack version the 398. These units have independent upper and lower sideband selection and have the best SSB tuning of any small portable.

From Dave Gibson on Cruising World message board:
Yachtboy 400PE: The radio looks a little cheap. It's got a silver coating on the plastic housing that looks like it will wear off in time.

Pushing the button to light the dial produces a puny weak glow. The display is still not readable in darkness.

The push button controls seem to be easy enough to use. It has an auto-search function that's nice, although it only scans up the frequency, not down.

The reception in upstate New York with both the telescoping antenna and the external wire is marginal. The shortwave stations seem to fade in and out, even the strong ones like the BBC. A good external antenna is a must in areas of poor reception, which is probably true of any radio, I guess.

The AM and FM work fine.

I paid $170 at Radios4You.com [in 12/2000 ?]. Their service was fine, but the warranty card was missing.

From Duke on Cruising World message board:
Yachtboy 400PE: AA batteries were cooked while operating with the transformer. Cooked two YB 400s so now I remove the batteries from my new YB 400PE whenever using the transformer. Not very impressed with either the quality or durability for the price. Features and availability are probably what sells them. Probably can do better for the money with a competitor.

My experience:
I use a Grundig YB400PE (successor is Grundig G4000A (on Amazon)), bought reconditioned. Works fine for shortwave; I've given up trying to get weatherfax. I use the radio without batteries, connecting it through a converter to ship's batteries. After a couple of years of use, the power connector has worn or become loose. Everything else is fine.

From George Barr on The Live-Aboard List:
The YB400 can be used for WFax reception by tuning to the USB mode using the switch on the side and using audio output jack to interface with one of the PC WFax programs. You will probably want a Y jack and headphone on the audio output so you can adjust the fine tuning of the FAX by listening to the broadcast as you input it into your PC.

From 1999 "Passport to World Band Radio":
In the Compact Portable category, top-rated radios are the Grundig Yacht Boy 400PE and Sony ICF-SW7600.

Try clipping a wire antenna onto the collapsed built-in telescoping antenna. This may be better/different from using the "external antenna" connector, which may have a desensitizing circuit attached to it. Radio Shack's 75-foot "SW Antenna Kit" for $10 or so is good.

From duffer on Cruising World message board:
Forget the Sony. SW 2001D has inherent design faults - antenna protection circuitry == none. The SW 77, what I own, typically loses its audio front end. Sony's response. Can't (read won't) repair. ...

From Buddy on Cal mailing list:
I have had both the Nav-Fax 200 and the Grundig Yachtboy 400. The Nav-Fax never did work very well at all. The Yachtboy 400 was a good radio but I ended up using a Radio Shack DX-392. This cost less than $200 and it has a cassette deck that you can use to record whatever you are listening to (such as a [voice] weather forecast) so you can play it back in case you missed something. I have used it on the boat now for 4 years and have had no problems from it. The model number is probably no longer any good but I am sure they still carry this kind of radio. [May be their version of the Sangean receiver ?]

From Rick Jendrysik on CompuServe's Sailing Forum:
I've been using the Sangean (Radio Shack version) for several years and have been very pleased with it. Whichever model of SW receiver you're looking at, make sure it is capable of fine tuning of both upper and lower sidebands. I use WEFAX software from Xaxero with their demodulator AND optional RF filter, which I would recommend if your faxes are the least bit garbled from a noisy PC. My faxes are almost as clear as those you can have e-mailed from NOAA.

If you plan on any winter cruising in the Bahamas, this setup will be invaluable. This past November we were getting 2 or 3 northers a week with the wind never going around and staying at 20-25 kts! I didn't move anywhere without first consulting the WEFAX. Every morning at 7:20 the radio was set to come on to 7096 LSB to listen to the Bahama Net weather, and then at 7:30, I'd switch to 12787 USB to start receiving the 24/36 hr wind/wave forecasts from NMG, out of Sidell, LA.

From Max Fletcher on Cruising World message board:
Rigging an antenna for portable SSB:

The Marion-Bermuda Race required us to have a SSB receiver; so I bought a basic one at Radio Shack, a Sony I believe. On the first trip to Bermuda I found the reception somewhat iffy, using the supplied 10 ft wire antenna stretched across the cabin. The next time we did the race I bought an antenna kit from Radio Shack consisting of a long copper wire with an insulator at each end. I stretched this from the masthead to the stern rail (parallel to the backstay), then ran a small insulated wire to the ext. ant. plug on the radio. I also ran a small wire from the ground screw on the radio and taped the other end to a bronze seacock.

The reception was MUCH MUCH better. I highly recommend this approach, which is simple and is very inexpensive and made a relatively cheap radio into a decent receiver.

H.F. Radio On Board

Note: some weatherfax directories list frequencies using the carrier frequency, and others list by USB frequency. They differ by 1.9 KHz.

Some weatherfax stations: Boston 6340 or 9110 KHz, New Orleans 4318 or 8504 or 12790 KHz, Cutler ME 20013 KHz.

For unattended/continuous operation, you'll be running radio and computer for hours. This may be a good reason to use a lower-power consumer receiver such as the Grundig G4000A (on Amazon), instead of a Marine SSB transceiver.

Typical getting-started problems:

How to receive it better:
Tips:

Typical problems:
From Rick Jendrysik on CompuServe's Sailing Forum:
Another thing to watch for, as it aggravates me to no end, is serial port interruption on your computer by Windows power management and/or the cooling fan. Unlike a modem, a radio will not resend data if your port is busy. I can disable PM, but the fan coming on will cause my fax to get out of sync. The only solution I have is to run cool.

From Jerald King on Cruising World message board:
I use Coretex about three times a week to receive WFX. I use a SONY SSB receiver at home with no antenna, a new ICOM 710RT on our boat, and an older ICOM 710 on my brother's boat. Both boats have 50' insulated backstay antennas.

We are in Tacoma, Washington, just south of Seattle. Our home is on top of the highest hill in the area, both our boats are in marinas surrounded by hills.

Sometimes I get a crystal clear signal on any of the sets. Sometimes I can receive no signal on any of the sets.

Signal reception is very dependent on the combination of time of day and time of year. Each WFX station broadcasts on four different frequencies from about 4 MHz to 20MHz. You have to try each frequency to see which is coming in best at that moment in time.

After your ear identifies the best frequency you have to tune down 1.9 KHz from the carrier (the published frequency) IF your set is receiving in USB (Upper Side Band Mode) or up 1.9 KHz if receiving in LSB mode. It is common that only one frequency will have a decent signal. In fact the highest frequency is only used during the day and the lowest at night.

However, those numbers are not absolute rules. In the late afternoon two days ago I was receiving the New Orleans USCG station perfectly but was tuned 2.2 KHz below the published frequency. You have to use your ear to find the best sounding tone, then use the Coretex Tuning Scope to get the best signal.

The quality of signal on a given frequency can change dramatically in a matter of seconds. When that happens I just try the next adjacent frequency. Again, the signal strength depends on time of day and frequency.

I use 5 MHz, 10MHz, 15MHz signals to help find the best WFX signal. Whichever time tick is clearest is a clue to which WFX frequency to start with. When 10 MHz is the best signal for time ticks I use the 8680 frequency for Pt. Reyes as my starting point.

Additionally you should note that the USCG does not adhere exactly to the published schedules, at least they don't start and stop at the right time when compared to Ft. Collins time ticks.

I have found that a change I make in the receive frequency, e.g. down 0.1 KHz, takes about 2 seconds to register on the Tuning Scope. That is with Coretex running on a 333 MHz Windows 98 processor. You can not tune real fast using the Coretex Tuning Scope - that is why your ears are the best starting point for tuning.

I have also found on the ICOM 710 that I often get better reception using the FSK mode than either USB or LSB.

During the last year I have received almost perfect signals from Boston, New Orleans, San Francisco USCG, Honolulu Metro, Kodiak USCG. I have sometimes gotten decent signals from Guam Navy.

SSB reception sometime has a skip zone in the 200 - 400 mile range. Is your receiver site within 200 - 400 miles of New Orleans ? If so try Boston or Pt. Reyes (San Francisco) because the signal in the skip zone may not be usable. The skip zone is also variable based on time of day, day of year, sun spots, and a lot of magic I don't understand.

Don't give up - I have gone days with no decent signal and then gotten perfect signals for days in a row. As I gain experience I find it easier to get the good signal. I can get a good signal about 50% of the time and a usable signal about 75% of the time using my new ICOM on my boat.

From Dave Gibson on Cruising World message board:
Finally ... I'm actually receiving a decent weatherfax!

Boy, what an ordeal for a weatherfax newbie.

I've got a PC (of course!), I bought a Grundig Yachtboy 400PE, and I downloaded the demo JVComm 32 weatherfax software. It's been a struggle, but this is what I've learned so far.

You've got to keep trying different weatherstations. Like an idiot, I'm figuring that NYC or Boston, being closest to me, would yield the best reception. Only after Frank, a denizen from Australia, asked me if I tried Halifax, did I try somewhere farther away. So, I set the radio for Halifax and watched TV with Jahnn for a hour. Just as I was checking my email for the last time tonight, a weatherfax was being received by JVComm.

It was coming in slightly better than the others, but still looked like a blueprint. That is, white writing on a black background. The station I was tuned into is at 6496.4 KhZ. From what I read, I'm supposed to tune in 1.9 KhZ below the published frequency, for some reason totally unclear to me. So I'm tuned in at 6495, the closest I can get to 6494.5 because the YB400 doesn't let me key in the decimal point. Just for fun, because I'm actually watching the fax come in on my monitor, I tune up to 6496 and it looks much, much better! Actually black writing on a white background. I then play around with the SSB fine tuning and the volume control (setting the radio up high and turning down the software setting) and it starts coming in really good.

And that's with the little stinky external antenna looped out a second story window.

...

I'm using a standard, simple Sound Blaster 16. I had to remove my simple ESS card, as the JVComm software didn't recognize it. And, like all software, I had to figure that part out for myself. It would be too much to ask to have the system display a message like "Unknown sound card. Get a new one".

I received about a dozen weatherfaxes last night. Some pretty good, others look like they shifted left or right quite a bit right in the middle. None are very good or excellent.

I think the secret is good antenna placement and a strong signal.

How to use the data:

I've pretty much given up on weatherfax. In the Florida Keys and Bahamas, it was fairly easy to receive voice weather info using the Grundig SSB receiver. I've never been able to receive a clear weatherfax (probably a better antenna would help a bit), they are very slow coming in, and I'm not going to leave radio and computer on for hours to get everything. Most people are getting info via internet instead, these days.





Email

Ways of doing messaging:
Systems: General characteristics:

Some specifics about each system:

Survey articles:
SailNet - Paul and Sheryl Shard's "E-Mail Options"
SailNet - Kathy Barron's "Sailing with E-Mail"
SailNet - Tom Wood's "Offshore Communications"
Voice and email article by Daniel Piltch in 3/2001 issue of Cruising World magazine.
Daniel Piltch's "Communication Options Comparison Chart"
HF email (mostly Winlink) article by Tim Queeney in Mar/Apr 2001 issue of Ocean Navigator magazine.
Email in Europe article by Walt Paul in Mar/Apr 2001 issue of Ocean Navigator magazine.
"Email at Sea" article by Dan Piltch and Tim Hasson in Sept 2004 issue of Ocean Navigator magazine
STO.P's "Email On Boats"
Heartsong III's "Recent Questions"
H.F. Radio On Board
Email On Boats booklet ($13 or $20)

More specific resources: Airmail

Book: Marti Brown's "HF Radio E-Mail For Idi-Yachts" (on Amazon)

To ask about any boat email system,
derived from letter by Don Melcher in July/Aug 1998 issue of Ocean Navigator magazine:

From Ed and Sue Kelly on Liveaboard list 8/2012:
We have used OCENS Satellite phone and email service and think they are tops.

We bought an Iridium 9555 Satellite phone, and also a stubby antenna we mounted externally and also a small Docking Station to keep the phone in that runs off of 12 volts at our inside steering station.

We have (except for a couple of test calls) always used the phone just for email. We installed it in April of 2011 just before our 38 sea days, going from Brunswick GA to Falmouth England in 2011. WORKED LIKE A CHARM.

We used the version of the software for Mac computers and it worked well. They spent time holding hands this July till I got it set up all over again from Serbia on the internet over SKYPE after I had removed prior software they had supplied. They are great at support, which I cannot say for others, as I found other service wanting and the principals at their competitors not interested in doing anything but selling you time and suggesting you just email them questions you have in setting it up. The competitors tried to give support with online videos, but they were not helpful. We switched back to OCENS because of this.

All emails are batched so that you compose them offline, and then when you log onto the mail program it compresses all outgoing and incoming messages. We would typically send as many as 8 simple email messages of text only in .7 or .8 of a second. This made it truly economical.

[Now travelling in Europe.]

Anyway, we thought we would switch services to an English satellite company (Mailasail) that serves many of the folks doing the Atlantic Rallye for Cruisers from the Canaries to St Lucia every year. We found the service not on a par, and the compression a joke compared to OCENS. After spending 50 minutes of precious Satellite time and doing just a few emails, we decided the savings from the compression of OCENS made their service far more economical in the long run. We have been using the Satellite phone from Central and Eastern Europe. I have heard good reports on the services with the Iridium equipment worldwide.

Winlink/NetLink:
Winlink does HF/VHF-to-Internet E-mail Text Transfer via NetLink.

Winlink Home Page

"Winlink 2000 is an Amateur Radio digital service that provides the automatic transfer of messages between Mobile Amateur Radio Operators World-wide and the Internet email System. K4CJX provides Internet email access for Maritime, RV and remotely located Amateur Radio operators, enabling those traveling to maintain contact with family and friends, regardless of location." Requires a ham radio General class license.

With Winlink, to send email from normal computer to mobile person:
"On the email address 'To:' or 'CC:' line, put the radio type email address as CallSign@winlink.org, where CallSign is the Amateur Radio station receiving the email message ..."

With Winlink, to get the latest position report for a mobile person:
Send email to qth@winlink.org, with subject POSITION QUERY and message body CallSign.
(No other characters in message body.)

From K4CJX on SSCA discussion boards 2/2001:
Because of increasing abuse from US and Canadian users of the Winlink 2000 Network System not holding a proper license, the following policy is now in force:

1. For any Amateur Radio operator using the Winlink 2000 Network not holding a class license that permits operations in the HF Ham bands, proof of any "special temporary authority" will be required.

2. For the Mexican Temporary Permit, such proof will come in the form of a copy of an Application Receipt or actual Permit. It is understood that most who apply for this permit do not receive it before they start operation. This is permissible as long as we have a copy of the actual application receipt.

3. For the IARU or CEPT permits, a copy of the permit is necessary.

4. Such license verification may be FAXED to Rick Muething, KN6KB at (321) 634-5838 or mailed to:
KN6KB
Rick Muething
6143 Anchor Lane
Rockledge, FL 32955

5. For those currently operating under a "Special Temporary Authority," a grace period of 10 days will be given.

6. Any station using the Winlink 2000 Network without a proper license who has not complied with the above request will be locked from the system upon discovery.

7. Exceptions always apply to serious emergency communications.

The Federal Communications Commission expressly directs those stations operating within their jurisdiction to be responsible for their own stations and apply the same principles of self-regulation as is expected with any other Amateur Radio Service. We do intend to comply and will extend this to the entire Winlink 2000 Network regardless of point-of-entry.

Airmail software is email client that supports Winlink and other networks.

Don Melcher of H.F. Radio On Board recommends:

From Pete on Cruising World message board, Jan 2000:
[IC-M710RT is] an excellent radio for doing Marine SSB email. I use the M710.

As far as the laptop goes, be sure it is capable of running Windows 95/98 so that it will be compatible with the Airmail software. It does not take a powerful computer; even a 486 running Win 95 will do the job. I happened to choose the Toshiba Satellite Pro 440CDX. I was told by people who repair laptops for a living to stick with Toshiba, IBM, or Compaq due to the ease of getting them repaired in remote areas. I also keep my laptop in a Pelican case (available at West Marine) with dessiccant when not in use. I expect that this will extend its lifetime considerably in the salt air.

You also need a specialized piece of equipment called the TNC (terminal node controller). There are 3 that I can recommend depending upon the price/performance tradeoff:
  1. Used Kantronics Kam Plus $150-$200
  2. New SCS PTC-iie $650
  3. New SCS PTC-ii $1000
The first TNC is very popular and reliable, but is quickly becoming obsolete since it only supports the Pactor 1 protocol. If you want to get your feet wet at minimum cost and upgrade later, as appropriate, then this is the way to go. Check out EBay for used Kams. If you want the ultimate in performance go with one of the SCS TNCs, both of which support Pactor 2. The major difference between items 2 and 3 is the fact that the more expensive one can remotely control your radio (which I recommend) and has an LCD display for additional status info. If you bought the iie, you can still remotely control your 710, but you would need a second COM port on your computer and a special cable with built-in level shifter. Again, for the ultimate in performance, I'd recommend item 1. You can check out the SCS TNC's at SCS. Kantronics is at Kantronics, but the workhorse Kam Plus has been phased out of production. Note: you can buy more expensive Kams that do Pactor 1, but I don't recommend buying new (and expensive) equipment that uses 'soon to be' obsolete technology.

Next, you'll have to decide if you want to go with 'free' ham email or 'pay as you go' commercial email. If you're clever, the equipment you select will work equally well for either (for this reason and others don't even think about PinOak/SeaWave). This allows you to start with a commercial service and then switch to ham if and when you get a license (Note: the FCC just announced that the Morse requirement will drop from 13 to 5 wpm effective April 2000 for the General class).

As far as the software goes, check out the Airmail pactor primer for ham email and the Sailmail pactor primer for commercial email. Airmail is free to all. It works with some commercial services because the service provider has licensed the software from the author, Jim Corenman. This software is great; it totally automates the process of sending and receiving email. In conjunction with the SCS TNC's it will scan all available frequencies (using remote control), pick a free one (using a built-in QRM detector), connect, and then automatically reduce the radio power to the lowest practical level (using the detected error rate).

On a related subject, the ham shore stations are now testing Winlink 2000 which will be rolled out in a few months. This software offers new features such as full binary uploads/downloads (eg, weather faxes), automatic position reporting, and full shared database across all shore stations so that you can send email via a shore station in Virginia and, if propagation happens to favors it, pick up the response from a shore station in San Juan, Puerto Rico!

As of early 2005, a new protocol "Winlink SCAMP" is being tested. It uses the CPU and sound card of a PC, instead of a TNC, to do email.

From Rick on Cruising World message board:
... digital e-mail can be loosely considered 100% duty cycle, but in reality is not ... also once the link is established "pactor" you can and should reduce power. Been doing this for a long time and send and receive most e-mail at less than 20 watts.






Content

Shortwave:
Listening to the shortwave is quite unlike listening to commercial FM radio in the USA. Stations often broadcast only a few hours a day, mainly in the morning and the evening, and often use different frequencies at different times. Some are using a single sideband, others are providing a full-band signal, which is just another variable to hassle with while trying to tune them in. Often the volume level and clarity "pulsate". Sometimes reception of a station will just "fade away" as you're listening to it. And there's always plenty of static and interference, especially near populated areas, near other cruising boats (from wind-generators, HF email, etc), and from your own boat (computer, alternator, auto-pilot, refrigerator, etc).

Stations which usually provide a good signal to the Caribbean:
BBC (5975, 6195, 9515, 9625 KHz). Also 9740 KHz at 0600-0800 AST.
VOA (15240 KHz).
American Forces Radio (all USB: 5446, 7812, 12133, 6350 KHz).

Other stations:
Radio Canada (5960, 6175, 9590, 17765, 17800 KHz).
Radio Havana (5965 KHz).
Radio Australia (6019 KHz).
Radio Netherlands (11655, 15315, 17725, 17735 KHz).

WWV time signals (2500, 5000, 10000, 15000, 20000 KHz).
Canada time signals (3330, 7335, 14670 KHz).

NPR Worldwide might be heard for a few hours a day on shortwave radio via American Forces Radio (all USB: 5446, 6350, 7812, 12133 KHz).
NPR Car Talk: Sunday 0500 Eastern, Tuesday 1100 Eastern ?
[BUT: As of 12/2005, AFN seems to have dropped all NPR content. And the standard AFN content is crap, geared toward the enlisted-man demographic.]

I use a Grundig Yachtboy 400PE receiver (successor is Grundig G4000A (on Amazon)); seems to work reasonably well. Extending the external antenna or hoisting it high doesn't seem to help much.


Marine VHF:


Joke cruiser's net page I created.

Marine HF Radio Nets:
Cruiser Log's Radio Nets
Amateur Radio Marine Nets
DockSide Radio's "cruising nets"

APRS (Automatic Position Reporting System):
From Larry KN4IM on rec.boats newsgroup:
We ham radio ops have a [distress / locating] system that works great and would cost $100/boat to install using present equipment. It's called APRS and it was invented by a ham at the Naval Academy to track lost midshipmen (most are lost, anyway) in the Academy's boat fleet. You can even watch the various APRS systems, LIVE, on the net at Bob's web-page.

If you left APRS running on your boat, currently on 10.151 MHz HF in the 30 meter ham band, anyone with net access, such as your friends and family, could simply go to Bob's web-page and see your current location on the Java running on their computer. APRS stations can keyboard with each other, report the weather, initiate a distress call, make announcements to the system, etc. ... It works TODAY. It works on HF, Marine VHF and we have "nodes" that even connect a local Marine VHF system to the worldwide HF system.

APRS Page
TAPR

NOAA Weather Radio (aka WX, NWR):
NOAA WX page

"... voice broadcasts of local and coastal marine forecasts on a continuous cycle"

"Most VHF marine radiotelephones have the ability to receive NOAA Weather Radio broadcasts."

"NWR requires a special radio receiver or scanner capable of picking up the signal. Broadcasts are found in the public service band at these seven frequencies (MHz):
162.400  162.425  162.450  162.475  162.500  162.525  162.550"
(These are out of range for most shortwave receivers.)

From Colin Woods on World-Cruising mailing list:
But for weather forecasts I must recommend the autoresponder service from http://www.buoyweather.com/ . For 10 US cents a message, you send them your lat and long and they send a text message back with a five-day forecast. They use the NOAA weather model.

You get great free reports from the web site, but the autoresponder is perfect for sailmail or other text mail systems.

Free email robot that sends GRIB weather files: send an empty message to info@saildocs.com to get instructions. Files also available from ugrib.

NAVTEX:
Text weather forecasts. 518 KHz. Requires a special radio receiver (typical shortwave radio doesn't receive this band).

Amateur Packet Radio:
Packet/email gateway: W2XO Home Page

Auto-Patch (connection from Ham Radio to public telephone system):
From Michael H on Cruising World message board:
... a 'patch' is a level converter that takes your received audio and resends it on a phone line and vice-versa with telephone audio. The ham running the 'patch' puts their ticket on the line that you won't commit an indiscretion on air.

I think the term 'auto-patch' may have its origins in a VOX (voice operated switch), so the ham doesn't have to monitor and hand switch transmit to receive.

From Ed on Cruising World message board:
Many hams have these; most are manual. The ham on shore will call the number, once they are on line, he must manually switch from transmit to receive; both parties should say "over". So, this is simply a one way, "simplex" call. There are legalities based on where the call originates (boat). Some countries do not allow this 3rd party type call; but no problem in international waters. Hams using repeaters on Marine VHF do use "auto patches". This is full duplex, just like a phone. But this is Marine VHF (line of sight) ...

From Bob Korte (I think) at a PAARA meeting:

Maybe have to do a collect call from the patching station to the person you're calling ?

From Rod Borchardt / KB2MRI, officer of a Ham club in New Jersey:
> I am planning to live on a sailboat in Florida.
> I have relatives in New Jersey.
> How could I go about finding a phone patch that
> would let me make occasional phone calls to my
> relatives ? Is it unrealistic to expect to find a
> patch I could use; are they rare or secret ?
> Would I have to join a club ? Or would no club want me,
> knowing that I just want to join so I can
> use the patch ? Would a patch support only collect
> or local calls ?
> Does your club run a phone patch ?

Most phone patches on repeaters are restricted to local calls, so I think you will have a lot of trouble there. I would contact the trustee of one of the local repeaters and mention to him what you would like to do. Your best bet is to use the internet (assuming your boat is in its slip). You can use dialpad or a similar program to make free phone calls.

From Don Wright / AA2F, member of Delaware Valley Radio Association in New Jersey:
You have phone patch and auto patch confused, as there is a big difference between them. The auto patch allows you to make phone calls from your 2 meter rig thru the local repeater and is generally for local calls only. You would not be able to reach our repeater [in NJ] from Florida on 2 meters. Phone patch is when you use your HF rig to talk to me on my HF rig and then I patch your signals into a box (a phone patch) that connects to my phone after I ring up your party on my phone, costing me whatever that phone call may (or may not cost). Your party here talks over their phone and you talk over your rig thru my rig and my patch. This obviously needs a prior schedule so that I am listening for you at a certain time and frequency for you to call me. The other alternative is for you to call CQ central NJ and hope someone in this area answers you and also hope that they have a phone patch and are willing to pay for a toll call to your party. I, like most hams, do not have a phone patch.

...

Anyone is welcome to join the DVRA. I sort of suspect that many members join only for the use of the repeater and autopatch. At least we never see them at meetings. You would have to be a member in order to get the codes to using the autopatch. The fee varies with your status - student, over 65, family member, member longer than 25 years, etc. It is currently $35/year for regular membership, if memory serves me rightly.


From Will on Cruising World message board:
... I suggest you also get your Ham license, and don't use it as most cruisers do: as a cheap source of phone patches to the States and email. In the most remote places there is always a Ham, their hospitality is the best. Most cruisers turn on their radio for the maritime net, get the email and weather then turn off the radio. Tune around looking for the locals and make contacts. Hams in remote places are very well-connected. ...

National Weather Service Marine Product Dissemination Info
NOAA links
USCG Maritime Telecommunications info
AC6V's Guide To Ham Radio Frequencies And General Frequency Listening

Good section on radio frequencies and schedules in "Reed's Nautical Almanac - Caribbean" (on Amazon).






Licenses For USA Boat


Need "Ship Radio Station License" if any of these are true:

Need "Restricted RadioTelephone Operator (RRTO) Permit" if any of these are true:

But lots of very experienced Caribbean cruisers have told me no Caribbean country has ever asked for these licenses when checking in. [As of 11/2004, there are rumors that Bahamas and Mexico are starting to ask for them. I have never been asked anything about radio or licenses in my Caribbean cruising from 2005 to 2011.]

FCC forms (ordering forms 800-418-3676, help filling out forms 800-225-5322):

BoatSafe's "Marine Radio Information for Boaters"
DockSide Radio's "FCC Radio Licenses"

From letter from Gary Jensen in 1/2003 issue of Seven Seas Cruising Association bulletin:
Fill out FCC forms on the internet, not via paper. It takes a long time on the internet, but it's faster and you know you're using the latest forms.

From Mike Y on Cruising World message board:
... [if] you have a Marine SSB aboard; for transmission in the marine HF radio bands you do need to have a Ship/Aircraft Radio Station License issued by the FCC. A prerequisite for the Marine SSB is that you have a Marine VHF radio as well. You cannot legally use the Marine SSB (for transmission) without an official call-sign, which is issued by the FCC as part of the Ship/Aircraft Radio Station license process.

The Ship/Aircraft Radio Station License is not an operator license. If you only have Marine VHF aboard, and you only cruise U.S. waters, you do not need the station license or an operator license. However, if you cruise outside the U.S., say to Canada or the Bahamas, you need the station license AND you need a Restricted Radiotelephone Operator Permit, also issued by the FCC.

From Dave Richardson on WorldCruising mailing list: "When voyaging out of the territorial USA save yourself any hassles on licensing Marine VHF, Marine SSB, and RADAR plus EPIRB registration by obtaining a US license. Just wave that official-looking document and you will normally be left alone."
And further clarification from Dave Richardson:
Bill, when I was referring to "US license" it was not Ham, although that would be preferred but only specifically for Ham and Marine SSB. For information on Ham or Amateur Radio licensing in the USA, go to the AARL site.

What I was referring to is a license issued by the US Federal Communications Commission. Although the Telecommunications Act of 1996 made it unnecessary to register or license a Marine VHF radio in the USA, this is not the case in many other countries. The UK and most of its possessions require a Marine VHF operators permit and license. Also in most countries Marine SSB is tightly licensed and controlled. In some cases RADAR must also be licensed. Here in Germany, I need a license for each TV in my house, car or boat. And of course EPIRB must be registered for it to be useful at all. It is amazing how many people buy an EPIRB and then forget that it needs to be registered. A DSC radio won't work unless it is enabled with a licensed code. Anyway, by submitting an application for Marine VHF (including each hand-held or portable as a separate item), Marine SSB, RADAR, SART, GPS, LORAN and EPIRB in the US, you will get back a formal one-page document or license listing all the equipment that it covers.

Next is the operator. If you plan to dock in a foreign port (e.g. Canada or the Bahamas), or if you communicate with foreign coast or ship stations, you must have a RESTRICTED RADIOTELEPHONE OPERATOR PERMIT (sometimes referred to by boaters as an "individual license") in addition to your ship radio station license. However, if (1) you merely plan to sail in domestic or international waters without docking in any foreign ports and without communicating with foreign coast stations, and (2) your radio operates only on Marine VHF frequencies, you do not need an operator permit. A ship radio station license authorizes radio equipment aboard a ship, while the restricted radiotelephone operator permit authorizes a specific person to communicate with foreign stations or use certain radio equipment (e.g., MF/HF single sideband radio or satellite radio).

You do not need to take a test to obtain this [restricted radiotelephone operator] permit. The FCC will mail the permit to you and it will be valid for your lifetime.

If/when an over-officious foreign official starts to give you trouble, this document usually covers you. Not a guarantee but at least a start.

From Rick Kennerly on the IRBS live-aboard mailing list:
HINT: if you're ever going to pay the $125 for an FCC station license for your boat, ALWAYS check EVERY box on the application and get listed for all the possible radio gizmos they offer. Amending the license costs $125, so even if you don't know what it is, check it yes and also have them issue you a digital selective calling number, even if you don't need it now.

From Rick Kennerly on the Yacht-L mailing list 12/2000:
By treaty we do require that both vessels and operators operating in international waters have radio licenses. However, it's not the USA that requires a boat to be licensed to operate Marine VHF (or other short-range safety-related radio transmitters -- RADAR, EPIRBs) in the territorial waters of another country. Instead, it's the radio regulations of the country visited that dictate which vessels, radios, and operators must be licensed and how -- just like we have a right to regulate the radio transmissions of foreign vessels in our waters. The treaty just unifies this process internationally so that if you and your vessel are licensed in, say, US waters, you don't have to get a license for every country you visit. Nor do boats from other countries have to get a US Marine VHF license when they visit here, unless they were unlicensed in the country of origin.

Many countries confiscate unlicensed "illegal" radio gear, so getting a US license is well worth the trouble (a form) and expense ($100), if you're cruising. Keep in mind that HF Ham and Marine SSB transmitters are viewed by many countries as being in unfair competition with the local telephone companies (especially those countries that own and generate revenues from the telephone company). So it's important to be on the right side of this issue.

There are side treaties between the US and Canada and, I think, Mexico about unlicensed boats operating Marine VHF type gear being used temporarily in each other's waters. However, once you leave US waters for an extended cruise, I'd really recommend that you and your vessel be in full treaty compliance. This includes a US FCC Station License for your vessel (hint - the license is about $100 [$200 in 2004, I think], but changes and amendments are $100, too. So on initial application mark all of the equipment, modes, and frequencies on the form, even if you don't know what they are or are not sure if you will ever need them. While you're at it, be sure to get a Selective Digital Calling ID assigned. Having to go back and add even one item will cost $100.) As I remember, Station Licenses are good for 10 years.

By treaty, each Marine VHF radio operator in international waters is also required to have an operator's permit or license. In the US this is called a Restricted Radiotelephone Operator's Permit (or higher if you're into commercial radio). These are $35 each [$75 in 2004, I think]. There is no test involved and these licenses are good for life. You should have at least one aboard. The regulatory philosophy is the same. Some countries require testing and fees to operate Marine VHF equipment but will recognize those licenses issued by other treaty countries.

Being recreational, HF Ham requirements vary a good deal and are not covered by the treaty that allows Marine VHF reciprocity. In some countries you must present your US Ham license to be issued a permit to operate in that country. Some test you. All require a fee. Once licensed, you usually append some letters to your US ham call sign to indicate what country you are transmitting from. Sometimes you're issued a whole new call-sign. FWIW, we're very strict in this country about foreign hams working HF from our shores, so the hassle in most cases is on both sides.

Even if you're not required to have a license (e.g. for Marine VHF in USA), you still have to follow the rules.

For regulations about a US Ham operator operating in foreign countries, see ARRL's "International Operating". For many European countries, you just have to carry the right documents. For some South American and Caribbean countries, you have to buy ($10/year) a permit through ARRL.

From Roy WP2F on the Baja Message Board 12/1999:
To be perfectly legal, you will need a Mexican Provisional Permit. (Mexico did not sign on to the recent reciprocal agreement of the Americas.) The permits can be obtained only in Mexico, usually in State Capitols. Tijuana, Mexicali, Ensenada, La Paz in Baja and many in the mainland including Hermasillo in Sonora. It's a hassle, but here are the basics. Take your just-obtained tourist card with at least 5 months remaining, and a copy of your valid U.S. ham license, to the office of the SCT. Depending on the political climate, you may be able to pay the fee (currently about $75 U.S.) on the spot, or you may be directed to a bank, in which case you will have to return with a receipt to get your permit. Your permit will be valid for the term of your tourist card. Think of it this way, for every dollar you spend, you get to watch as an official stamps something! Now the good news: For ANY class of U.S. license, you get full band privileges for voice in Mexico. A no-code Tech can use voice even in the CW portions! AND, you get to use a neat Mexican prefix to your U.S. callsign, like XE2 or XF1.






Installation and Operation On Boat


SailNet - Sue and Larry's "Choosing and Installing an SSB Radio"
Eric Steinberg's "SSB/HF Radio Applications in Modern Sailing Vessels" (PDF version)
Vic Poor's "HF Radio EMail Installation: How To Do It On A Small Boat"
A Sailmail Primer
Gordon West's "Marine SSB Single Sideband Simplified"
SGC's "General HF Tech Notes"
BoatU.S.'s Marine VHF "Antennas"
Chris Caswell's "What's Up With [Marine VHF] Antennas"
"Better Radio" article by Andrew Bray in 1/2001 issue of 48 North

"Seven Seas Cruising Association publishes a booklet 'An Installation Guide for The Maritime Mobile Ham'. If you are a member you can order it ..."

"... download [from Airmail Downloads] and install Airmail 2.x9 software on your PC. You will find that the built-in help menu gives all the details on how to hookup a variety of TNC's to a variety of radios. ..."

General choices:
A boat antenna system can be either: The active antenna element(s) can be: If using an unbalanced antenna, the ground (counterpoise) can be:

Antenna stuff:
From Craig Johnston on the SailNet liveaboard-list:
... all antennas consist of two parts. Some, such as dipoles, have two similar parts in the air. Others, such as long-wire antennas, use the "ground" as the other part of the antenna. Your boat probably had a long-wire antenna using the backstay, a very common arrangement. Since the length of the insulated backstay (plus its feed-wire, which is part of it) is not exactly correct for a given frequency, a tuner is used to electrically modify the antenna ("load it") for a given band. Sailboats variously use internal copper foil, engine and keel, external ground plates, or combinations of the above to achieve the necessary ground. One thing is sure -- the radiation of the antenna will only be as good as the ground. ...

From Peter Linwick on Cruising World message board:
The best way to get good reception from your Marine SSB definitely is to isolate your backstay. The ideal length for Marine SSB antenna is between 27 and 40 feet. ... the upper insulator needs to be approximately 3 feet down from the mast head. The lower insulator must be placed out of reach of anyone standing on deck. ... Having a tuner should be a must.

"Insulating the backstay involves removing it and having 2 insulators (made by Sta-Lok, Norseman and others) installed by yourself or your friendly local rigger."

Maybe can use small lengths of rope as insulators in the backstay ?

Keep the backstay insulators and the wire-to-backstay connection clean, to avoid RF power leakage.

The backstay-antenna should be as long as possible, but out of reach from deck (for safety), and stop 3 to 5 feet from the top (to keep mast and other rigging from affecting it).

From Norm on The Live-Aboard List:
Definitely insulate both ends of the antenna [even with a wooden mast]. In fact, two insulators at each end are twice as good as one. It's the length of the leakage path that counts. It would be swell if you had a hose you could use to wash the salt off the insulators before transmitting.

On my first trip to sea, on a tugboat across the Pacific, I had to carry fresh water up to the roof of the pilothouse and wash the salt off my insulators before I could get enough juice into the antenna to transmit.

The wire from the antenna tuner to the backstay-antenna is really part of the antenna too. You don't want to route it right along or through metal objects or wires, including the backstay-antenna itself. Use stand-offs to space it away from the backstay and backstay-antenna.

From James Maynard on The Live-Aboard List:
... I recommend an antenna coupler that is NOT designed as part of, or to work with, only one brand of radio. An antenna coupler that is sold as part of the Marine SSB installation will be expensive, and will work only with that brand of Marine SSB radio. Likewise, an antenna "tuner" that is part of a ham radio won't help you when you need to use the Marine SSB. In general, avoid an antenna tuner that is built into the radio itself, because the tuner is really part of the antenna. You really should separate the antenna and its coupler from the operating position, in order to minimize the electrical noise you feed into the antenna and therefore into the receiver. Also to minimize the amount of RF energy you feed into other circuitry on the boat when you transmit. The ideal -- not really achievable on a boat -- is to have the antenna far from the cabin, the antenna coupler at the antenna, and shielded transmission line (coaxial cable) connecting the two, with RF currents confined to the INSIDE of the coax. (Currents on the outside of the coax can be suppressed with ferrite chokes placed around the cable.) That separates the antenna, when receiving, from noise generated in the cabin. And it separates the antenna, when transmitting, from the cabin, so as to minimize the bad effects of your transmitted signal's getting into other circuitry on board. ...

From Brian Woloshin on Cruising World message board:
Don't use coax from tuner to antenna. The antenna feedline should be a single, stranded, heavily insulated wire, not coax. The antenna tuner should be located below deck as close to the backstay as possible. Using a coax feedline introduces its own impedance that has to be matched to the antenna. A single wire feedline is actually part of the antenna. The purpose of an antenna tuner is to match the radio's impedance, 50 ohms, with the impedance of the antenna, which varies by frequency.
From Will on Cruising World message board:
Good advice. Strip the coax shield from thick coax like RG213, the centre insulation has about a 5000 volt breakdown rating and is UV resistant. The main reason why you don't use coax from tuner to the antenna is that the coax has capacitance. This capacitance shunts your power and causes excess power loss. Backstay insulators all have capacitance, but nobody talks about that. This capacitance does cause problems depending on the length and frequency of the antenna.

From Marvin Gordon on Yacht-L mailing list:
HF antenna wiring: what you want is your automatic tuner / antenna coupler as close to the backstay as possible, and from the output terminal of the tuner/coupler you want insulated VERY high voltage antenna wire (usually about 14 or 16 gauge) led to a point on your backstay just above the insulator (Norseman or Sta-Lok make great insulators that will hold MORE than the rated capacity of your rigging wire). You CANNOT use coax for this part of your antenna lead. You do NOT want to try to solder or weld this wire to your backstay under ANY circumstances as this will damage the characteristics and working strength of the stay big time. Most radio shops and some marine wardware stores will sell a properly sized bronze cable clamp that will clamp the wire to the stay very effectively. Tin the end of the antenna wire with a little solder and then use a little emery cloth to polish up the clamp areas on the stay, the clamp and the tinned wire; put them together and you're in business.

From Rick on Yacht-L mailing list:
Rather than a mechanical connection, the radioman's way is a properly constructed seizing.

1. Above the bottom insulator, polish up about a foot of backstay with fine grit (100, 220, something like that) wet and dry sandpaper.

2. Bare about a foot of GTO-15 (a 50-ohm wire made for this kind of connection).

3. Take the GTO-15 and make a "U" shape in the wire (on the insulated part) just above where you've bared the copper. Secure this bend with a UV resistant cable tie to the backstay (or a twist of SS Monel seizing wire). Ensure that the loop or bottom of the "U" is pointing up (so that the exposed open end of the insulation is pointed down -- keeps water from seeping down the core of the GTO-15 to your tuner).

4. Optional, but not a bad idea: Get a tube of copper paste from West Marine (it's in the radio section). Smear the polished section of the backstay with the paste.

5. Unlay the bare strands of copper wire on the GTO-15 and begin to wrap the strands around the backstay in a tight spiral, being sure to lay the copper in the grooves of the backstay wire. Make it compact and tight so that you only use up about 6" of wire. Smear the outside of this joint with the copper paste.

6. Get some SS Monel seizing wire from the boat store. Seize the copper GTO-15 to the backstay using the SS wire, making nice, tight wraps.

7. Rebuild every year or so.

From George Day's radio article in Blue Water Sailing magazine:
For HF: A dipole is a much better antenna than a long-wire (backstay) or whip antenna, but much harder to rig on a boat (and antenna tuner must be near center of it).

From "Safety Preparations for Cruising" by Jeremy R. Hood (on Amazon):
Connecting the tuner wire to the backstay: wrap 2 inches of the backstay tightly with Monel seizing wire, bare 2 inches of the tuner wire and lay it over the Monel, wrap tightly with another layer of Monel, then wrap with waterproof rigging tape.

From Peter Hendrick:
... we designed and built two (redundant) HF antennas, neither of which use a ground plane. They perform substantially better than the bottom-fed insulated backstay we started out with and create much less interference to our other electronics. We're still pulling out the old (and corroded) copper foil we originally installed in '97!

The first antenna is specialized. It works only on 20 meters. It turns out that 95% of my ham email connections are done on this band so I'm very interested in it. It consists of two 'Ham Stick' loaded whip antennas placed back-to-back (using special adapter) to create a loaded balanced dipole antenna. As a balanced antenna it uses no ground plane. This antenna is mounted at the masthead with an athwartship orientation. The overall width is about 15 feet as I recall. This antenna requires no tuner and connects directly to the Marine SSB through 75 feet of coax cable. The antenna creates zero interference onboard while transmitting. As I recall the total cost was about $50 excluding coax cable.

The second antenna is what I call a multiband simulated inverted-V dipole antenna. It again is balanced and hence requires no ground plane. It has been tested and works well on 80, 40, 30, 20 and 15 meters. The two elements are created from the forestay and backstay. The two elements are connected to a 4:1 current balun (Radio Works model B4-2KX) at masthead. The balun is connected to the tuner via 75 feet of coax. I use the normal ICOM AT130 tuner which is not designed to drive a dipole, but was dipole, but was from my (now defunct) bottom-fed insulated backstay. The backstay is insulated and the forestay is not. I purchased several very thick books on antennas (I recommend the ARRL Antenna book) and also consulted with 3 different expert hams before building these antennas. One ham even ran computer simulations and predicted superior performance on all bands. This antenna tends to interfere with onboard electronics minimally. The prior bottom-fed insulated backstay created significant interference.

...

the two big benefits were better performance and lower interference. One negative was two new coax cables running up the inside of mast.

Mel Neale says a 23-foot whip antenna and a ground plate works fine for their Marine SSB.

Outbacker short HF antenna ($300+)
RopeAntenna (dipole inside a rope, hoisted by a halyard ? $185)

Marine VHF antenna:
See EBay's "VHF Marine Radio Antenna Buying Guide"

A high-gain (9 dB) antenna may be worse than a low-gain (3 dB) antenna because a high-gain antenna probably is more directional. The best is a low-gain antenna mounted as high as possible.

Sizes: 3 feet long == 3 dB,
8 feet long == 6 dB,
20 feet long == 9 dB.

Cable: small diameter cable is okay for runs less than 20 feet,
use RG-8X or similar for longer runs,
use RG-8U or RG213 for 50 feet or more.


Emergency Marine VHF antenna: piece of coax with braid and innner conductor on one end peeled back to make dipole antenna .465 m on each side.

From Max on Cruising World message board:
SSB receiver offshore:

The Marion-Bermuda Race required us to have a SSB receiver; so I bought a basic Sony at Radio Shack. On the first trip to Bermuda I found the reception somewhat iffy, using the supplied 10 ft wire antenna stretched across the cabin. The next time we did the race I bought an antenna kit from Radio Shack consisting of a long copper wire with an insulator at each end. I stretched this from the masthead to the stern rail (parallel to the backstay), then ran a small insulated wire to the ext. ant. plug on the radio. I also ran a small wire from the ground screw on the radio and taped the other end to a bronze seacock.

The reception was MUCH MUCH better. I highly recommend this approach, which is simple and is very inexpensive and made a relatively cheap radio into a decent receiver.

From Dave Skolnick on The Live-Aboard List:
> Is there any simple way to test the integrity
> of a Marine VHF antenna and its cable, short of buying
> an SWR meter or something ?

If you are just trying to trace cables, you can temporarily short one end and use an ohmmeter or multimeter to check the other end. If you want to check the match (which will usually tell you about water intrusion as well) you really need a VSWR meter designed for VHF. I'd expect to pay $50-75 for a good (not great) one. DON'T use a CB meter a la Radio Shack. It must say VHF; you're looking for coverage between 155-160 MHz. If you go to a hamfest (a radio-dominated flea market for geeks) you can probably find one for $20. If you keep your eyes peeled for ham radio license plates (or cars with an unreasonable number of antennae sprouting from the trunk lid and roof) around the dock you can probably get the loan of one for free (heck I can see three SWR meters from here, but I'm in Virginia) and technical assistance for a beer.
From Sidney Patin:
By testing the integrity of the Marine VHF antenna, I assume you are referring to whether it has continuity in the antenna, feed line and transmitter connections. Best way to test that is with a multimeter. An SWR meter will give you power out vs reflected power, and is a really good investment if you want to keep your radios running in top condition and tuned properly. MFJ Enterprises in Mississippi has some decent meters for VHF for under $50, I think. I have their MFJ-864, which works on HF/VHF/UHF frequencies, and I use it all the time with my ham rig at home.

From Gordon West in 1/2006 issue of Sail magazine:
Most masthead VHF antennas have a base loading coil that will appear to be shorted on a simple ohmmeter test, because the coil is shunt fed [so the antenna can't be tested that way].

West Marine's "VHF Antennas"
Dipole antenna article by James Baldwin in Cruising World magazine Feb 1999 issue.
Marine VHF whip antennas reviewed in 7/15/2000 issue of Practical Sailor.

Ground (counterpoise) stuff:
Several different "styles" of this, with advocates for each:
From "Seawater Grounding for High-Frequency Radios" article by Gordon West in 10/2001 issue of Sail magazine:

From Scott Adam on the SailNet liveaboard-list:
... The critical ground point is to have the ground plate as close to the antenna tuner as possible. At least that is what Gordon West says. ...

From Larry KN4IM on rec.boats.cruising newsgroup:
If you're cruising at sea, with nothing much to do, and want to improve your HF communications grounding A LOT, try trailing a long piece of wire (longer IS better) over the stern and hook it to the ground point on your HF antenna tuner. Trail out 100-200 feet of any kind of conductor, insulated or not, into the sea. The tuning of the whole antenna system will change, so it'll take your auto-tuner a few seconds to find the new tuning point. You'll see a lot better coverage with a trailing wire.

From BobM on Cruising World message board:
Even if you use one or more external ground plates like the Dynaplate, you should always connect them to your transmitter and antenna tuner with WIDE copper foil since RF energy travels mostly over the surface of a conductor. More surface area, more energy conducted. Since you already will need to run the flat copper down to the bilge (where your bolts for a dynaplate are) you have done the toughest part of a foil ground already.

The Dynaplate makes a good DC ground but RF energy will pass thru a damp hull fairly easily without the need to poke holes and bolts in it first.

A case for external plates might be made for a boat with no engine or metal ballast or tanks (i.e. large metal objects), but for most cruising boats, a far better RF ground will be created by running two or more 3' or 4' flat copper straps along the hull interior below the waterline. All straps should be bonded together by soldering carefully. Coating the foil with epoxy or even varnish will help to reduce corrosion.

"You can purchase 12-inch copper flashing by the pound at roofing supply houses ..."

From the Dashews: "You want to have your ground plane located as close to the antenna coupler as possible - hopefully the coupler will be right in the middle. Once you get a quarter wavelength or so away from the coupler the ground plane becomes useless."

Dipole antenna doesn't need a ground/counterpoise ?

From Brian Woloshin on Cruising World message board:
Getting the grounding system right is the most difficult part of a Marine SSB install. What size is your boat? Do you have an external keel that you can tie into? Internal keel would help also but sometimes they are hard to connect to (no keel bolts). You were right to skip the dynaplate, they do not work for SSB.

The best thing to do is tie your keel and engine together with flat copper at least two inches wide. If you have the room to layout flat copper radials against your hull do that as well. Find copper from someplace other than West Marine, their price is ridiculous and the copper is thinner than I prefer. Thickness means corrosion resistance and thus longer life. As Ed said copper mesh will quickly corrode away in your bilge.

The most critical part of the ground is where it attaches to the antenna tuner which should be located as close to the feedpoint of your backstay as you can get while still protected from the weather.

Moonraker's "Earth Systems"
Icom's "Grounding and Antenna Considerations"
Gordon West's "Seawater Grounding For HF Radios"

From John / Truelove on The Live-Aboard List:
After messing up my bilges with foil and bonding several thru-hulls together (the advice of Ham guru Gordon West) with fair results, I called SEA and asked for a recommendation. They said to run a separate ground foil from the transceiver and one from the coupler, both terminating at one point on the engine block. I did, and voila! SWR is usually 1:1 on all bands except 2 MHz (which no one uses) and 4 MHz, where it is always less than 1.3.

From Jerry Peters on World-Cruising mailing list:
In order for the SSB counterpoise [foil] to be effective it needs to be below the waterline even though it is not in direct contact with the water.

From Jeff Smith on The Live-Aboard List:
When I installed a Ham radio on my boat, I received all kinds of (sometimes conflicting) suggestions. I quickly came to realize that it's a bit of a "black art" and that trial and error seems to rule a bit. And frankly, some of the suggestions were so labor-intensive that they seemed hopeless to me. Some people seemed to think that unless I lined the entire hull from stem to stern with copper foil I would never get a signal out.

In the end, I installed a tuner in the stern locker, and "temporarily" tied the ground from the tuner to the aluminium steering quadrant using heavy 2" wide, tinned copper braid. It's about 1/8" thick I believe and runs about 3 feet to the from tuner to quandrant. My intent was to use that for a while until I hauled and then install a dynaplate and copper foil everywhere.

First night I fired up the radio and my very first chat was with a guy in Tennessee (I am in Toronto). My next chat was with a guy in central Nebraska. BOTH individuals confirmed that my signal was very strong and the quality was in both cases reported as "it's like you're sitting beside me."

So far, I haven't seen any need to change anything at all. Never had a problem getting 1000-mile-plus connections at 50W power. My antenna is a copper wire up the back, strung between the backstays and tied off to the end of the bracket for my windvane. I put insulators top and bottom and simply clamped a #6 tinned copper wire to the copper antenna wire using a wire rope clip. The other end of the #6 is tied to the tuner. Really simple and cheap.

If I were to do it over again (and I probably will someday when I get another boat) I will for sure start out with the minimum amount of work and see what happens. If it's not satisfactory I would then keep fiddling until it gets to where I am happy.

Will on Cruising World message board advocates a "balanced-radial" antenna:
... The ground should really replicate the top portion of your antenna. The ground acts as a current return to the antenna making it work properly. The best and simplest solution is simply to connect a ground wire that is resonant on each marine and ham band. You calculate this by using 234/frequency. If you can fit 2 radials from the lug of your tuner and sneak and zig zag this in your boat to fit. [Don't connect it to anything, especially not engine and keel.] ... Mesh and thick copper foil is a waste of time on most voltage-fed antennas ... Simply connect resonant wires using the above formulas to your antenna tuner, you can use [plastic-coated] very thin tin-plated wire. That's all; no magic, no foil, mesh dyna plates or other Voodoo. ...

[Again:]

one or two wires [more is better] for each of the marine or ham bands:
2 MHz = 117 feet can also be 62 feet
4 MHz = 58 feet
6 = 39 feet
7 = 33 feet
8 = 29 you can skip above if you're using ham 7 MHz
12 = 20 feet
14 = 17 feet

Just simply attach one or two of the above lengths to your tuner ground lug and sneak in the wires wherever you can, zigzagging and folding back is okay. That's all you need for the best RF ground. The wire can be thin plastic coated tin plated wire.

Forget about foil, copper mesh and dyna plates.
From SGC's "HF SSB User's Guide", about balanced-radial antenna:
... The best ground starts with wire radials longer than the antenna and at least the same size or larger in diameter than the antenna wire. ...

If reception is good but transmission is weak, suspect a poor ground connection or too little ground plane area.

From letter by Gary Davis in July/Aug 1998 issue of Ocean Navigator magazine:
"Given a properly functioning antenna coupler, a low SWR on one HF band and a high SWR on another HF band indicates a poor RF ground system."

Good grounding is harder in fresh water than in salt water.

From Charles Freeman on the SailNet Caribbean Islands list:
A lot of what you hear about *grounding* is old wives tales; i.e. no scientific basis for support. Gordon West recently did a scientific test of three methods: (1) Grounding ribbon inside the hull using the capacitive effect to seawater. (2) Grounding via Dynaplate to seawater. (3) Grounding via a single bronze thruhull to seawater. Measured were effective radiated power at a distance and tuned VSWR.

Results: Dynaplate did not perform any better than a single thruhull. Both were far better than grounding ribbon.

Recommendation: Grounding to a single thruhull is perfectly adequate as a counterpoise to a longwire antenna with a tuner. Most important is short length of grounding ribbon from TUNER to thruhull. (Don't ground the radio, let the TUNER do it, or you get ground loops).


Cable stuff:
Along with the cable to the antenna, the cables from the radio to the antenna tuner are pretty important, too. For example, bad connectors or long length can sap power.

Cable from radio to antenna tuner: connect shield at radio end only. This drains any induced RFI to radio chassis ground, and avoids ground loop between devices.

Cables bought from Icom are expensive and made of inferior materials ?

Paraphrased from "The Boatowners Mechanical and Electrical Manual" by Nigel Calder (on Amazon) (I think):
Coax cable:

Also: coax should use 95% tinned braid.

From Jobst Vandrey on Cruising World message board:
Whatever unit you install, make sure that the [DC] wire run to the SSB powerhead is as short as possible and use OVERSIZE cables. The SSB will draw at least 25 amps at full transmit power and even a small additional voltage drop caused by poor connections or undersized cables may result in an unstable transmit frequency that could disrupt communications (especially with email modems).

Moonraker's "Signal Cabling"
Moonraker's "RF Connectors"

From Rufus Laggren on the IRBS live-aboard mailing list:
The major manufacturers have booklets providing good generic advice. I don't know enough to give any decent advice about construction, but the following is generic info from a TransPac seminar last month.

The antenna is *not* just the antenna, but rather a system composed of 5 or 6 parts.
- - antenna
- - antenna ground plane
- - antenna feed wire from tuner
- - feed wire from amplifier to tuner
- - feed wire from transmitter to amp (if applicable)
- - all long metal things within about 1/4 wavelength of the antenna (!); this includes the power leads to your transmitter if you're not careful.

Any and all of these parts are capable of completely screwing you, so pay at least token attention to each of them.

Although most of it can be faked up with tin foil and coat hangers if you're good enough, coax cable cannot be - at least without lots of time to do it over again in a year. If you use coax, you need to start with the best cable you can get and the best terminals; if you're not *very* good with a soldering iron, then have them professionally installed by the most reputable shop you can find and afford. Pay lots of attention to water proofing the end at the antenna. Cables that *look* OK but are *not* cause a lot of the grief, trauma, and tragedy found around radios.

If you run a cable up inside a mast or RADAR pole, or whatever, make sure the connections allow you to pull the mast without cutting the cable.

From Airmail/Winlink talk in George Town Exumas 3/2002:

Operating tips:
World Wide Repeaters

Don't use "squelch" with marine SSB; there is little or no carrier for the squelch to monitor, so it will cut off the beginnings of words.

[Much of this from on Logan S/V Scotty Ann Cruising World message board:]
To receive weatherfax:

From Michael H on Cruising World message board:
There are a number of propagation forecasting programs available ...

You need to input the solar activity, which is transmitted hourly by WWV and WWVH, your position, and, depending on the program used, the position of the other station (some programs build a world model, some build a 24 hour 'picture' to a specific location, some do both).

I've used them during ham radio 'contests', which is a good test because there are so many stations on the air, and have found them to be very good predictors of when which bands/locations will open and close.

Broadcasts:






Radio-Frequency Interference (RFI)


Jim Corenman's "Solving RF Interference Problems"
Article by Larry Douglas in 2001-#3 issue of DIY Boat Owner magazine
Article in 1/15/2000 issue of Practical Sailor

Mostly from "The Boat Repair Manual" by George Buchanan (on Amazon), and Clymer "Powerboat Maintenance Manual" (on Amazon):
Propagation of interference: Suppression of interference: Sounds of interference through a radio:

From article by Larry Douglas in 2001-#3 issue of DIY Boat Owner magazine:

From article in 1/15/2000 issue of Practical Sailor:

Paraphrased from instructions that came with MFJ-701 choke kit:
In a multi-wire cable, common-mode currents are those that are not balanced by an equal flow in the opposite direction within other wires of the same cable. A common-mode choke works by providing higher impedance, dampening those currents. Currents that are balanced by an equal flow in the opposite direction are called differential mode, can cause RFI, and are not affected by common-mode chokes. Filters or shielding may be necessary in those cases.

From Rick Kennerly on IRBS live-aboard mailing list:
Most times, RFI is transmitted up the powerline instead of directly through the antenna of radios. Good chokes (ferrous magnets that the power lines are coiled around and through) are available through ham radio stores as are choke beads that slide onto wire like a necklace. It's not uncommon in Marine SSB and Ham installations to have to choke not only the SSB radio itself but also nearly every other piece of electronics with a power line on board. Laptops are particularly difficult to shield, especially those with plastic cases. In today's world where every device has a "chip" (and all electronic chips "whistle" at some frequency) nearly every electrical device has a built-in RFI generator.

Of course then the next line of defense (and a step up in costs) are filters of one type or another.

The display of my Dell Inspiron 1100 laptop generates RFI that I can hear in the shortwave radio. During booting, I can hear the RFI go away when the display is blanked and come back when the display is lit again. Both laptop and radio are powered through DC-DC converters attached to the house batteries. RFI goes away if laptop is unplugged from power converter.

From Will on Cruising World message board, about radio generating a lot of RFI that affects other equipment:
The first symptom of this syndrome is a bad RF ground. Improving your RF ground will reduce some of the potential problems. The next problem is the antenna, most marine backstays are typically "voltage-fed", and in some cases they are current-fed depending on frequency. The best way to check for this is to see if the interference occurs on all the marine bands. If it occurs only on 1 or 2 marine bands, just increasing the length of your antenna slightly will cure the problem. This can be done simply by increasing the feed from your tuner to the backstay. This condition varies from frequency to frequency, and is dependent on antenna length. Shortening the antenna also helps. Choosing the correct antenna backstay length can be done with a bit of forethought but most seem to think that longer is better, when in reality a shorter antenna would work better in most cases. This shorter antenna will lower the impedance and lower the voltage field. Ever wonder why huge battle carriers that have acres of real estate in most cases use a 35 foot whip for HF command and control? The answer is voltage, since the power they run 20,000 watts up, would present a huge engineering problem since the voltages would be so high. The potential to cause interference on sensitive instruments would be huge. The next area of concern is that the RF near field is basically above your equipment, meaning the current and voltage density is high close to the RF source. Unfortunately most marine consumer electronic equipment is not electromagnetic compliant, so you will just have to suffer the consequences. Buying equipment that is FCC approved or approved for use in Europe under the EMC directive is a good idea. This is what separates professional equipment from everyday marine electronic junk. You can try and cure the problems using common mode chokes, this simply involves wrapping the HF radio's power and antenna cable around some Amidon 43 ferrite rings, this can also be done for your bilge pump and other critical items that are going berserk. Flashing LED's and other lamps can be simply cured with 0.01 uf ceramic capacitor across the power line near the LED or lamp. This capacitor will also work well on bilge pumps. I would be very careful on aluminum boats because many of these capacitors on multiple circuits could cause stray currents. You can buy ready made chokes from companies like Radioworks, but there's nothing to these devices. Making your own will save you money. An antenna current Balun consisting of several ferrite beads of the Type 77 material placed at the antenna tuner will choke off any stray currents that will feedback into the DC system. Unfortunately this is typically what has to be done on all electronic installations for them to work correctly in the presence of RF fields, its just a shame that the companies who make this equipment don't do their jobs properly at the design stages. All it takes is a 1 dollar's worth of parts, and good design techniques. My boat is loaded with ferrites and I have zero problems and I run 600 watts on my HF system. All these problems can be cured if you have the desire to do so ...

From Colin Foster on Cruising World message board:
If you are certain RFI is coming from the alternator, what you need is a bypass capacitor on it. You need one rated for at least 50 volts and 1000 microfarad minimum. It is connected with the positive output of the alternator connected to the positive terminal of the [electrolytic] capacitor and the negative terminal of the capacitor goes to the frame of the alternator. The trick is to get it right on the alternator which means some good mechanical mounting to keep vibration from moving the leads too much. Use stranded leads to replace the solid leads on the capacitor if it doesn't have screw terminals. When I say "get it right on the alternator" I mean that the leads from the capacitor must be as short as absolutely possible - less than 2 inches maximum - an inch on each lead is better.

From Richard Goodwin on The Live-Aboard List:
There are two (at least) sources of spikes from a starter: Brush noise, and a big spike when you let off the starter button and the solenoid breaks contact. Brush noise can be transmitted through the air as well. Other sources of spikes or "noise" are: turning on or off any electrical switch, especially a switch to an inductive load like a motor, motor brushes, generator brushes, alternator or other charger pulsating DC voltage output, ignition point break if you have a gasoline engine with mechanical distributor.

The above are sources of noise directly on the power line itself. Noise also can be induced in the power lines from outside sources, such as spark plug wires, brushes, switch sparks, any sparks, lightning in the vicinity, 120v power lines, ignition from passing vehicles, etc.

Most noise can be minimized by putting a suitably sized capacitor between +12 and ground, and/or by putting an inductor in series with the +12 line. The size of the capacitor or inductor depends on the frequency and amplitude of noise. To absorb a really big inductive voltage spike, such as from point break or starter solenoid break would require a larger capacitor than small motor brush noise.

A typical filter for electronic devices such as radios can be installed close to the radio itself, and consists of a capacitor between +12 and ground, plus an inductor in series with the +12 line. The inductor resists passing higher frequency noise, and the capacitor shorts the higher frequency noise to ground. Many mobile electronics units have such filtering built in to the unit itself or into their power line connection.

Noise generated by a starter or other motor can be filtered at the source, since that will protect the rest of the +12 system. Generators and points, e.g., have capacitors to ground from their +12 connections.

Noise elimination can be as much of an art as a science in some cases. Success depends on discovering the source(s) of the noise(s), and putting in the right kind of filtering. To protect against large inductive spikes such as from a starter you need a large capacitor to absorb the energy of the spike before it gets into your electronics. It might be easier and safer to just disconnect the sensitive loads first, since starting can involve dramatic variations in battery voltage that cannot be filtered out.

From John / Truelove on the WorldCruising mailing list:
... No matter who does the auto-pilot install, insist on shielded power cables throughout; don't be talked out of it by the dealer. This is the key to heading off problems with AP noise in your SSB as well as the SSB knocking the AP out of "auto" when you xmit.

About Marine SSB producing RFI that affects laptop computer,
from Michael Yorke on Cruising World message board:
With the proximity of the radio to the computer a couple of things could be happening. The RF field generated by the radio could be entering the computer via external cables, such as the power cable, or it could be just completely overwhelming the circuitry on the circuit boards inside the computer. As a starting point I would suggest purchasing a couple of ferrite cores (Radio Shack, or similar outlet) and wrapping the AC power cable around and through them. Probably need several turns. The ferrite cores and the wraps of AC power cable form a filter that will keep RF energy out of the computer, assuming (a) that the cable was the point of entry, and (b) that the RF field is not so intense that it will overwhelm the filter as well. If you have an externally connected mouse, try the same ferrite core treatment. The other thing that you could try is to add a low pass filter to the output of your SSB transmitter. The low pass filter (try a ham radio store) allows HF frequencies to pass through, but attenuates higher frequencies. If the higher frequencies are the cause of the laptop interference then the LPF will help. If not ...

No guarantee that these suggestions will work. Sometimes RF problems can be intractable. On my boat transmitting at certain frequencies will set off the AC ground protection units, on other boats the RF will upset the autopilot. In my home amateur radio station I have computers in close proximity with high power HF amplifiers and with a combination of low pass filters on the transmitters and amplifiers and ferrites on power lines I have no problems.
From Rick on Cruising World message board:
Concur but also add: Could have a SWR problem that is not detected. Do you have an adequate RF ground, not DC but RF ? Have similar set up and no RFI, but sometimes gets into the stereo, and the tach on engine control ...
From Dick Giddings on Cruising World message board:
And one more idea ... I know the laptop is seven feet from the transceiver, but ... how close is it to the antenna lead routing? Almost as significant. The other suggestions are all rich with probability.
From SG on Cruising World message board:
Beyond Mike's and Rick's comments, a couple of questions:

i) If you disconnect the [laptop] charger AC (or DC) connection and transmit would the mouse go for a "walk"?

ii) If you disconnect the interface with the NMEA(s) (GPS and/or autopilot and/or other interfaces) does the same thing happen? -- You may be getting a "feed" because of some improper grounding of another device or it's peripherals.

iii) Are you using an external mouse or other device for the portable? If so, disconnect and see what happens.

iv) I trust that you aren't using the software that controls the Icom 710 from your PC. Similarly you don't mention it, but are you using a (Pactor or other) modem to receive weather FAX's? You might try to see if you disconnect those and see if the situation continues.

v) If you get this phenomenon from an isolated RF transmitter, then maybe you might try checking to see if you could ground the chassis of the PC. SOME portables have provisions for grounding the chassis of the portable. If not, you could try an alligator clip to a good ground and see if it helps.

(By the way, my "new" Dell has a Ferrite filter on the AC charger unit. I haven't noticed interference.)

From Greg on Cruising World message board:
Most of those ferrites sold at Mouser etc are type 43 material, designed to stop low frequency noise. Yes, you can use them, but you need a lot of them to achieve the same performance as one good core.

The ideal material is type 77; this is specifically designed for HF attenuation. A 2 to 3 inch core is all you need.

You can read and find all the technical data at CWS ByteMark's "Magnetics and Ferromagnetics Materials"

Fair-Rite has the best HF material called 31. Don't buy the wrong material; you are just wasting your money.

[Also:
Allied Electronics
FerriShield
Mouser Electronics
palomar-engineers
RF Parts
Universal Radio
]

From Paul on BoaterEd message board:
For those of you that have had trouble with your VHF-FM, stereo, or other electronics with video displays giving a buzzing noise or static on the video, here is the fix:

Get a piece of 8 or 10 gauge wire long enough to go from the frig to a good ground buss bar. Connect one end to the casing of the frig. Twist the wire around the hot and ground DC power leads (and the AC wiring if you can) for as much of their run as you can. Connect the other end to the ground buss.

Summarized from Gordon West in 7/2005 issue of Sail magazine:
RFI from Danfoss controller in refrigerator:
Wrap compressor and controller in copper foil and ground it onto the compressor's metal mounting legs.
Also put chokes on the control wires coming out of the controller, as close as possible to the plastic controller box.
Also, wrap controller box with copper screen from a hardware store.

Radio Shack sells a couple of types of chokes. What is listed on their web site doesn't always match what is in their stores; look in both places.

From Gordon West in 11/2008 issue of Sail magazine:
A battery monitor with LED display will produce RFI from its "LED chopper circuits", and is always on.






Web Access From Boat


Web access over HF radio is impractical (expensive equipment, slow, interference, size limits); go ashore and use cyber-cafes or libraries.

Some people point out that someone could capture your keystrokes or access your cookies after you use a public computer (at a cyber-cafe or library), getting your account and password information. The risk does exist, but I've been using public computers for years with no problems. Personally, I'm comfortable with it. I think it's more likely that some waiter or cashier would copy your credit card info and misuse that.

From Leslie Fournier on Yacht-L mailing list:
We used a lot of i-net cafes ... We DID contract viruses. Some places would scan your disk before they'd let you bring it in but most didn't. I think we got 2-3 viruses while in Mexico and maybe one in Costa Rica, which took down our computer.

Libraries:
Most USA libraries offer free internet access, with no library card needed. Smaller branches may have few machines.

Printing usually costs 10 to 20 cents per page.

Various libraries have time limits on Internet use (if someone is waiting), usually 30 to 60 minutes.

Usually the wait to get a machine is 0 to 20 minutes, but a few times I've had to wait 45 to 90 minutes.

Many/most libraries restrict application use to just a browser (no text editor, DOS command line, FTP, etc). But sometimes you can launch a text editor from IE browser by doing a "view source" on a web page. My last-resort access to FTP is to email files to someone else who can do an FTP from their computer for me.

Most libraries I've used have had floppy drives available in the computers. Some say "no floppy disks allowed".

From Barry Brazier on the WorldCruising mailing list:
[Re: email at sea:]

Cyber Cafes are widespread but costs are not so cheap in some places. The cost is limited by the cost of phone connections that the internet has to use. In Ecuador and Tahiti it can be as much as $5/min. The cafes charge for connection time. Even if you have your mail on disk it takes more than one min to get organized. May be $25 min charge. In some cases it is cheaper to send a short fax. Less than A4 size can be less than a 1 min.

From Jan Thoelke on the WorldCruising mailing list, 7/2000:
There are Cybercafes everywhere in the Caribbean, if that's where you plan to go. Only the Bahamas are somewhat of a Black Hole in regards to modern communications, as Internet hook up is outrageously expensive there.

On the island of Providenciales in the Turks and Caicos group, you will find Internet kiosks even in the supermarkets!

In the Dominican Republic, the Codatel offices provide cheap Internet access through their own PCs, or you could hook up your laptop.

The US Virgin Islands are covered, the BVI are terrible and far too expensive for Internet.

In St. Maarten you enter again modern territory, with affordable Internet everywhere, even at anchor, if you wish.
From Colin W on the WorldCruising mailing list, 7/2000:
There are a couple of cybercafes in Nassau which cost $5 per half hour and work fine.
My experience of Bahamas cyber-cafes 3/2002:
Bimini: 20 cents/minute;
Nassau: 10 cents/minute;
Black Point: 10 cents/minute;
George Town Exumas 50 cents/minute.

No cafes anywhere else in Exumas.

All links slow except in Nassau.

From Janet Hartman on the Workaboard mailing list:
Re: phone lines

> However, it is exceedingly common now for marinas to offer internet
> connections - either through a formal set-up, where there is a
> specific place for cruisers to bring their laptops and plug in, or
> informally where you use the fax or credit card machine line. There
> is almost nowhere on the ICW from the Chesapeake down to Key West
> where this is not possible.

Don't count on it. We went down the ICW from NJ to NC. Even if you consider the ICW starting in VA, not all places let me connect. At more than one place, the pay phones were also temporarily out of order or non-existent. Cruising between RI and DE we found the same thing.

At some places, unless you are talking to the "person in charge", people don't know if it is ok to let you use the fax line. This happened to me at the Alligator River marina. They advertised a fax line available for cruisers, but the guy in the office would not let me connect my laptop. I checked multiple times, but the person in charge had not returned, so I could not use the line.

Most places do have a place to connect, but you may not be able to get to it. Some connections are outside, so if it is very cold or raining, you and your laptop may not be very happy. The biggest limitation I found is that if you are borrowing a phone line inside an office, such as a fax line, you can only get to it when they let you during business hours. In many cases, before 8:00 AM or after 5:00 PM you are out of luck. The best places are those with a connection in a lounge or laundry area that you can get to at any time. So if you call ahead for a marina, don't just ask if they have a phone line - ask them where it is.

The phone line at the dock in Oriental that both Rosalie and I mentioned does have a wrinkle. It is actually a shared line with the office, so you can get interruptions.

Some places with a line you can use have it set up to work only with 800 numbers. Local calls will not go through. In order to use a phone card or credit card, I sometimes needed to plug in my regular phone to see what the problem was. In Coinjock, this allowed me to determine that the directions the marina gave me to get an outside line were incorrect. In Beaufort, this showed me that the processing was just slower - I had to put more commas in my dialing sequence to slow it down. Sometimes, I have used a splitter to plug in the phone and laptop simultaneously to get things to work. When you count on a phone line for work purposes, you will try almost anything!

What I am going to do is get a new cell phone that I can use with the laptop so I have another option when I am cruising. It is too expensive for routine work use, but it will give me a lot more freedom when I am cruising. For the total east coast coverage that I need, Verizon seems to be the most reliable according to other cruisers. The nearest office is a 2 hour drive away, so I have not done it yet.

Not sure of this:
If you are using a foreign-owned computer in a cyber-cafe in a foreign country, it won't have strong encryption installed on it (because of USA export rules). Thus you can't access secure web-sites (using SSL; pages named *.shtml). So you probably can't access your brokerage account, your bank account, etc.
But from Chuck Morford on the WorldCruising mailing list:
I used a PC at a Cyber Cafe in Ukraine earlier this year [2000] to trade stocks in my brokerage account. A site CAN require 128 bit encryption to make secure transactions, but in my experience they will generally work just fine with the 56 bit encryption generally available outside the US. Also, earlier this year the State Dept removed the export restrictions on "strong" encryption software, so you're likely to find 128 bit encryption in places that have taken the time to update their software.
My experience: no problem from the Bahamas in 2002, no problem in Dominican Republic in 2005.

Retrieve web pages (with HTML and images stripped off) via email: STO.P's ATOLWEB

Cell-phone with MODEM: only near shore, limited coverage areas, maybe 9600 baud, not cheap.

Satellite-based systems: DirecPC, StarBand (Cringely article about StarBand).
But hard to stabilize satellite dish on boat (maybe use Marine-Sat SkyWatch or Follow Me TV, but only good for calm conditions).
DSLreports.com

From Frank Timpano on The Live-Aboard List, 9/2002:
Satellite internet [e.g. KVH] can only be done from a boat with an active pointing system. Antenna pointing must be very precise, and even tied in a slip, without a tracking method, it wouldn't work unless you had the antenna mounted on the dock. Requires much more accuracy than DirecTV. Also, since it is a transmitter as well as a receiver, it requires FCC certified installer, and must be 5 feet above any area where people might walk (to avoid the RF radiation). The antenna is heavy, 70 lbs (30kg) or so. I have this system, DirecWay / AmericanSatellite (formally DirecPC) by Hughes Satellite Systems at home. About $60/month.

I've used DirecTV on my boat and even with static pointing (ie, clamped to the bow rail), tied in a slip it works pretty well. Would only work at anchor with a pointing system, FollowMe TV is the least expensive alternative for calm anchorages.
From Eric Thompson on The Live-Aboard List, 9/2002:
The dish weighs about 70 pounds. It measures 23 X 39 inches. The FCC requires the installation be performed by a licensed technician. This IS included in the $580 purchase price. They have a plan where you pay $99 a month for a year to pay off the dish, modem, and installation and then you revert to whatever the rate is when it is paid off.

It IS useless for anybody not at a fixed location due to VERY tight aiming requirements. No currently available 'stabilization platform' that is at all financially reasonable can keep the dish aimed NEARLY well enough. They will not estimate speed. There is even a bandwidth-limiting plan to restrict people downloading too many megabytes in any one day to try and assure "fair bandwidth sharing".

Wi-Fi (AKA "WiFi"; short-range wireless internet; 802.11; 2.4 GHz):


Antenna configurations:
  1. Antenna built into your laptop.
  2. Antenna built into Wi-Fi card inserted into your laptop.
  3. Add a Wi-Fi "remote booster" box to configurations 1 or 2.
    This box receives and retransmits the Wi-Fi signal, at higher power.
  4. External antenna with wire that plugs into Wi-Fi card inserted into your laptop.
  5. Same as configuration 4, but use a high-gain (directional) external antenna instead of an omnidirectional external antenna.
  6. Antenna/Wi-Fi (client bridge) box with an Ethernet or USB cable that plugs into your laptop.

Short range: usually 75 to 300 feet. May be able to improve it with a better antenna on your laptop. Or make your own: How To Build A Tin Can Waveguide Wi-Fi Antenna.

Maybe want a directional antenna, rather than an omnidirectional antenna. Gives stronger signal and more range, but must keep it pointed at the access point.

Some antenna vendors:
FAB Corp
NetGate
RadioLabs
hField Wi-Fire

Client bridges / remote antenna systems:
Port Network's Marine Wireless Bridge 200 (Ethernet)
WaveRV Marine 300 remote antenna system (USB)
Wi-Fi Networking for Cruising Sailboats
IslandTime Marine Wi-Fi System
Ubiquity NanoStation

Wi-Fi article by Ralph Naranjo in Jan/Feb 2008 issue of Ocean Navigator magazine
mv.VikingStar's writeup on Ubiquiti Bullet plus router

From Vern on The Live-Aboard List:
My experience with amplifiers and antennas on the boat have not been very good. I found much better gain by using a USB wireless adapter mounted on a parabolic such as a chinese wok skimmer. All the amplifier does is amplify the noise on weak signal. Amplifiers work OK if you have a good strong signal that doesn't quite make it as far as you want. They really work better on the Access Point side than on the receiving (client) side.

From Steve on The Live-Aboard List:
I recently bought an Orinoco gold card. I coupled it with a "Cantenna" I bought on sale at CompUSA. It made a HUGE difference in reception for my laptop. I went from marginal reception some of the time (and none the rest of the time) to solid reception all the time. And this with the Cantenna inside my sailboat, not outside.

From Jim Maynard on The Live-Aboard List:
It's the antenna that makes the difference! When you use the built-in antenna in a laptop that has Wi-Fi built-in, that built-in antenna (in the Panasonic toughbooks, it's at the top of the display) is generally better positioned that the antenna that comes as part of a PC card (such as the Orinoco card). But if you connect to an external antenna (e.g., Orinoco card connected to an external "cantenna"), that external antenna will usually work better yet.

My experience:
I bought an Orinoco gold card and "Cantenna" 7/2006.

Reception (with external antenna) seemed good in some cases, worse than my 3Com card in other cases, and required constant fiddling as the boat swung at anchor in other cases. Definitely a mixed bag.

The software with the Orinoco card is pretty crappy, and they don't provide updated drivers. The reception of the card (without external antenna) is worse than the reception of my 3Com card.

Cantenna has spots of rust on it by 11/2006 or so.

2/2007, the coax wire on the Cantenna snapped off, and it looks unrepairable.

I ended up buying a Blueproton GSky 500 mW USB adapter (on Amazon), and am much happier with it.

But I went through a couple of Blueproton GSky's, killing one by dropping it. Less happy with it 2/2011; I'm going to try something else.

Bought a Rosewill model RNX-N2LX; seems to work pretty well. Runs a little hot; maybe all of them do.

Then 7/2012 I went to a Ubiquiti Bullet BM2-HP system. Laptop ethernet cable and 12V connect to a little POE (Power Over Ethernet) box. Ethernet cable from POE to the Bullet. Antenna cable from Bullet to Engenius EAG-2408 antenna.

The bad things: The Bullet doesn't seem to "see" any more networks than my Rosewill USB adapter did. The Bullet is very tricky to configure, and the company supports only professional installers; they don't support end users. The Bullet uses its own browser-based UI, not the Windows "Networks" tray icon, so switching from one network to another takes a lot more clicks. The Bullet and its UI are really intended for permanent point-to-point links, not end-user use. For example, you get no feedback if your Wi-Fi password is wrong, and the Windows tray icon doesn't show you what network you're connected to at the moment, and there's no way to say "connect to whichever of networks A, B and C are available at the moment". The Bullet runs hot; keep it out of the sun. I paid around US$150 for the whole Bullet setup, compared to US$35 or so for a USB-based adapter such as Rosewill.

The good things: The Bullet is physically more convenient. Ethernet lets the laptop be a lot further from the antenna, and the vertical rod antenna holds onto the signal when my boat swings. Much better than the USB-type adapters in these ways.

Don't change the upper byte of the Bullet's MAC address; some bits in there have special meanings, and setting them wrong may make the Bullet stop connecting (learned the hard way).

From Bob Stewart on The Live-Aboard List 10/2006:
The best Wi-Fi adapter around right now is the EUB-362ext. This is a USB adapter that has a high output (200mw) and a very high receive sensitivity (-96dbm @ 1Mbps).

This adapter gives you a large range of options for deployment. The most basic would involve temporarily placing the adapter as high as you can using a USB extension cable.

With the 2 dbi antenna included with the unit you'll get very good results with the adapter sitting on top of the dodger. With the RP-SMA jack you can move up to 5, 7, or 9 dbi rubber duck antennas. Just about any antenna you want to use can be easily attached to the adapter. If you need to use it when the weather is inclement you can use a zip-lock bag to temporarily weatherproof it.

This adapter is physically better than a PCMCIA card because you can keep the external antenna close to the adapter and because the RP-SMA jack is more robust than the jacks on PCMCIA cards.

From Jim Richardson on The Live-Aboard List:
Take a Wi-Fi gateway, like a Linksys WRT54-GL, then reflash the firmware, put it up the mast. Connect your laptop's *wired* ethernet port to the gateway, and use that as your route to wireless nirvana. Obviously, this is a little more technical that most folks are comfortable with. But if you want directions on how to do this, a great place to start is www.openwrt.org
From Jeremy White on The Live-Aboard List:
I second that approach. We have the WRT-54G up the mast now, using power-over-ethernet, and can see quite far.
From Zed on The Live-Aboard List:
The older Linksys WRT54G units are the best little boxes. They are easy to modify (both hardware and software).

Unfortunately the newer model WRT54G's no longer run Linux and cannot be modified in the same manner.
From Jim Richardson on The Live-Aboard List:
Get the WRT54GL, it still runs linux, and you can reflash the G to run a stripped down OpenWRT but you do lose features compared to the full OpenWRT (more features than the stock Linksys firmware however).

From David White on World-Cruising mailing list 9/2009:
I have experience with about 5 different [Wi-Fi bridge] units. The [Ubiquity] Nano2 right now is the best bang for the buck. The Nano uses a cat5 [Ethernet] cable instead of USB. The USB is limited to about 20 feet from the computer the cat5 is more like 100 feet. You could stick it on the mast. Although with Wi-Fi that might not be the best for short range reception. It also has an n connector so you can add an additional antenna. The Nano's directional antenna is about 60 degrees of coverage. This should allow for considerable boat swing. For the price of an omnidirectional antenna you could in theory get 360 degrees op coverage, with a higher db gain. The longest distance I have received and sent a signal, (remember it has to be a two-way connection) was nine miles over the water. The Nano comes in a small weatherproof housing.

We have also used the RV Wave from Radio Labs. This antenna is also all-in-one, omni-directional, but uses a USB cable It's great for RV's but has limited use on a boat because the computer is usually located below deck.

If there is a hard part, it's the initial setup.

From Ken on "Silverheels 3" 3/2012:
This is the system we love: IslandTime Marine Wi-Fi System ($239 + $16).

We have the Bullet and it's an Ethernet-based system, so a longish Ethernet cable from the PC to the 8 dB antenna and 1 watt transceiver is not an issue. It can be mounted up in the rigging but we don't like it thrashing around up there and so have mounted it permanently on the bimini frame. Rikky from De Big Fish in Grenada sells the same unit.

It is a complete package along with a long waterproof outdoor cable, a shorter indoor cable (both Ethernet) and a POE (Power Over Ethernet) box which supplies 12 VDC ship's power to the system. IslandTime's standard system is mounted to a pipe or other vertical strut with two U-bolts. For another $30 he provides a unit that mounts on the end of a standard 1"-14 thread marine antenna fitting. The Ethernet cable can then be routed inside the support tube, then into the boat.

We ordered a 35-foot cable which is 10 feet longer because we thought that the antenna and transceiver needed to be mounted on the spreader or somewhere higher. It works very well where we have mounted it on the bimini, nicely away from mains'l halyards and other lines.

We added the $55 wireless router which eliminates a cable to the laptop PC. This is the best system we've seen anywhere.

We leave everything powered up all the time. Our Blackberry uses it, plus two laptops and two Kindles at the same time.

We've made a guest account on the router with a simplified password which we loan to friends anchored nearby who have difficulty seeing a shore-based Wi-Fi provider.

The wireless router is transparent in the system. The laptop connects to the router full time. You address the Ubiquiti Bullet unit directly on your browser. There is no software at all resident on your PC, it's all password-protected on the Bullet and on the router.

Rikky's system is identical but the slightly higher prices reflects his Grenada delivery costs. However, Rikky is a business here, and you have a warranty with a local. Our warranty guy is in Florida. Just a bit further. However, IslandTime is a cruiser too and he gave me loads of online advice and emailed system updates to us as well so I can recommend him without any reservations.

Alternatively, you can buy the Bullet transceiver module from a distributor in the USA. The manufacturer is Ubiquiti. The distributors are hard to deal with over such a long distance and you'll still need to source the 8 dB collinear antenna, a waterproof gland for the bottom of the Wi-Fi transceiver and the outdoor Ethernet cable. Then you'll need to make an Ethernet junction box to supply 12 VDC to the cable.

Budget Marine sells a similar Ethernet system called Bad Boy. The finished system seems pretty pricey.

In our opinion, these Ethernet-based systems have killed the market for USB Wi-Fi adapters, which are limited in output power and cable length by the 5 VDC power available on USB.

...

[A friend experimented with Wi-Fi antenna height above the water, and concluded that on top of dodger was best.]

High-powered Wi-Fi USB adapters:
Alfa 1000 mW with 9 dBi omni antenna (on Amazon).
BlueProton GSky 500 mW (on Amazon).
BlueProton GSky 1000 mW with 9 dBi omni antenna (on Amazon).
Rosewill RNX-N2LX (on Amazon).
EnGenius EUB362 (on Amazon).
Radiolabs Wave Magnum Wi-Fi USB Adapter 1000 mW (on Amazon).
the Wirie ($225; uses the Alfa)

More internet cafes are offering Wi-Fi access: you bring your laptop in to the cafe, and use Wi-Fi to connect. Some coffee-shops and bookstores are offering free access: you bring your laptop, and buy coffee and snacks from them as you use the internet. Some airports and libraries also have free hot-spots.

Near large apartment buildings, you often can find unprotected free access just by sitting on a curb with your laptop.

A new standard coming out, 802.11n, is supposed to increase range and speed.

Wi-Fi (2.4 GHz) signal is vulnerable to interference from Ham or marine SSB radio, cordless phones, baby monitors, microwave ovens, and security cameras. And RFI from alternator, inverter, RADAR, refrigerator, etc.





Signals


There are several ranges of signals (not very scientifically presented here):

TypeFrequencyWavelength
X-raysnear 1017Hznear 10-9 meters
Visible lightnear 1014Hznear 10-7 meters
Microwavesnear 1010 Hznear 1 centimeter
Radioin high KHz and MHzin meters
Audiblein Hz and low KHznear 105 meters
Home ACin Hznear 107 meters

How Stuff Works' "How the Radio Spectrum Works"

Apparently, the term "Shortwave Radio" just means "using the Radio signal range, usually for audio".

TV, cell-phones, satellite phones also use the Radio signal range but are not considered part of "Shortwave Radio".

From letter by Ed Callaway in Summer 2006 issue of Invention & Technology magazine:
One of the lesser-known wonders of the wireless age is the sensitivity of everyday radio receivers. The average car radio, for example, can successfully receive signals of several billionths of a watt.







Bookmark and Share

Home
Site Map     


Privacy policy