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 Through radio we have met a great number of friends and become a part of the community. We get advice, weather information, find old friends and meet new ones through the radio. Whether Ham radio or SSB, the short wave radio is the only reasonably reliable form of communications on board over the horizon. You can get a very slow email service but one which has truly global coverage. Cell phones work only when near the towers and we finally dumped our Globalstar sat phone because it was so flaky in the southern Caribbean. Furthermore, cell phones and sat phones do not have the more social properties of the party line. When inquiring about the weather up island, an acquaintance in your own anchorage can break in and invite you over for sundowners.
We bought an ICOM 706 MKIIg, Pactor III modem and AT4 antenna tuner in our very first season and carried it with us to the BVI. The Pactor III modem is required only if you need email but it is also helpful for retrieving radio fax. We had already worked out the software:airmail for email and jvcomm for weather fax at home. The cabling between the radio and the TNC (radio modem) is arcane and we got pre made cables from HF Radio on Board in Alameda as well as the TNC and a lot of good advice. I had had a ham radio license since an early age and a HAM radio was a clear choice for us. It costs about half what an Marine SSB Radio costs and it has a tuning dial which all geeks prefer to the "user friendly" push button Marine SSB. We also made a small modification to allow this HAM radio to transmit on Marine SSB channels.We have not had occasion to operate the transmitter on SSB (which would not be strictly legal) but thought it would be good to have the capability to do so in case of emergency (which is legal). If you do not have a HAM license from the FCC, you must buy a Marine SSB and use a pay service for the HF Email but the following installation advice will be similarly applicable. Marine SSB has a great deal of lively traffic and will be a lot easier to operate in case of emergency. Get a license (no exam required) from the FCC.
Standard advice for installing a HF Radio on board your boat involves two big steps:
- Cut the backstay near the stern and near the top of the mast and install insulators to make that isolated section your vertical antenna
- Drill a hole in your hull and install a "ground shoe" to serve as the transmitter's ground
This is the way professionals will install your radio and it will involve a haul out and a rigger (to cut the backstay and install the insulators). This sort of installation will not exhibit individual variation among boats and is therefore a good choice from the point of view of the installer. I may be a radio geek but I am a sailor first and weakening the standing rigging or putting holes in the hull are not something I can do casually. Furthermore, I am a cheapskate and prefer to spend my money on the toys and not the experts.
The following advice was given to me by an electrical engineer only after I had satisfactorily answered the following questions:
- Are you a lawyer?
- Do you ever have lawyers on board?
The risk in this method of installation is that you might have a passenger or crew member holding on to the rigging while you are transmitting. I have not actually performed the experiment but I believe that it might result in a burn depending on the frequency and duration of your transmission. But what do I know? I am not an electrical engineer. I am not a lawyer. You are not paying for this advice. Use at your own risk! Not to be used as a personal floatation device. Not intended for human consumption & so on.
 Basically the modern antenna tuners can match a dull axe to your transmitter and make it serve as an antenna. This method will require that you get the antenna tuner that matches your radio, not a manual tuner. Manual tuners will probably not be workable. This tuner comes from ICOM and has one coaxial cable bringing the signal and one control cable for the radio to cause the tuner to tune the antenna to the current frequency of your radio. The other connections are a ground strap to the "ground" (discussed below) which is the slightly corroded copper strap attached at the bottom and seen in the background climbing up to the bolts holding the toe rail on the hull The antenna is connected at the wing nut at the top and is the dark, round, single conductor high voltage wire passing to the right in the picture over to the chainplate of one of the backstays. The box itself is mounted on the aft side of the aft bulkhead of the starboard side cabin. This tuner has been sitting in the rather damp aft lazerette for 5 yars in the tropics and has only needed replacement of the antenna feed which corroded through.
The notion is to use the whole rig as a kind of antenna known as a delta. If the mast or the standing rigging is not electrically bonded to toe rail or to the boat ground and your boat is plastic (fiberglass), the entire rig can be used as "the antenna". . We ran high voltage wire (insulated somewhat like spark plug wire) from the tuner "antenna" lug to the bolts projecting through the transom from the chainplate of the backstay inside the stern lazerette on the starboard side near where the tuner is installed.
A better name for this portion of the antenna system is "the counter poise ". The signal needs to push off of something. In a dipole, the ground does not play a role because the two halves of the dipole push against each other. With a whip (the long white antennas sold by Shakespeare) some conductive body serves as the other half. If you have a metal boat - you will have a great signal because you have such a great counter poise. The "ground" side of the antenna tuner is attached to hull and the signal (antenna) side is attached to a whip at least 23' long. . If you are on land, you can bury wires radiating out from the pole, place wire mesh around the base of the antenna or place the whip in the center of your mobile home (or other metal structure) Alternatively, you can go to an antenna design that has both radiating element and counterpoise up in the air. Dyna plate will tell you some hocus occurs about activated nodules replacing a huge spread of metal under the whip with a little 20 square inch shoe in contact with the sea water. It will work but not much better than throwing a little bit of copper foil overboard. We did that the first season and it worked fine. The sea is an adequate but weak counterpoise. This is messy and very hard on the copper foil which immediately begins to corrode. Some have tried bonding the ground to a metal through hull and this seems to work ok. My concern is in the potential for corrosion around the through hull.
We run the traditional heavy copper foil from one toe rail at the stern of the boat, across the antenna tuner "ground" lug and to the other stern end of the toe rail. Before deciding on this method, I checked with a Multi-meter to see that there was no short between the toe rails and the standing rigging. It was while doing this that I found that the two toe rails (port and starboard sides) were not bonded. The foil running across the back of the boat also presents some more area of counterpoise. If you are ever in a position to influence boat builders (or are building your own hull) ask for a copper mesh to be embedded in the hull itself. The copper lying around in the boat is a constant source of corruption.
 I mounted the radio on a well-used cutting board to which I applied non-slip matting. This not only avoided making a square hole in the nav station's power panel, it also put the knob in a position more comfortable for me to operate. As my panel is at right angles to the seat, mounting it in the panel would have had me twisting to one side to see the dial. Be sure to use very heavy power cable from the radio to your batteries. Poor signals seem to commonly result from excessive voltage drop in the power supply cable. This little unit is fantastic. No complaints, many kudos to ICOM.
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