Join Date: May 2001
Thanked 0 Times in 0 Posts
Rep Power: 15
SSB Ground - Any Dynaplate Users?
Here''s a specific answer to your question & also some differing opinion from what you''ve already received:
1. We were forced to rely primarily on a Dynaplate for our counterpoise on a previous boat. We too got consistently good signal reports but that often means little (see below) and I''m sure that we could have had better xmit performance if we''d access to more mass below. So...it will work but isn''t THE answer.
2. Newmar usually makes good stuff, and perhaps the ''shoe'' is comparable to a Dynaplate, but most likely not ''the'' answer, either.
3. Signal reports for one install method are - regretably - a terrible way to determine how to install your system. This doesn''t have to do with the honesty of the reporter, but rather the typically poor form of signal reports offered on Marine SSB. (I''ve yet to hear one Marine SSB user give a report based on the one common baseline method - RST - that''s in use, so who knows what ''good'' is?) Ham operators are usually better about this only because they tend (at least in some cases) to know something about radio operation & procedure. So...my point is that its tough to know which choices to make based on what I or someone else will tell you about how great our radio works. (OTOH, I have a GREAT radio installation...!<g>)
4. Here''s the approach I''d recommend for your counterpoise. Start simple, running 4" or wider foil (sold by the foot by Defender; good price) in the bilge from the tuner, forward to whatever largest metal mass(es) you can reach that are not in turn tied into your 12V negative ground. (Read each piece of that sentence, again). Don''t overlook using your lead keel, as encapsulated lead keels can often be reached by drilling a hole down thru the fiberglass cap and then using a lag screw to tie it to the foil. Be creative. E.g., one great additive source of a counterpoise are the half-oval stainless strips on rub rails. If you fell you must install a dynaplate at this point, you may not be trying hard enough. Now - after the inevitable teeth-cutting problems as you learn how to work your radio - determine with the help of multiple knowledgeable signal reports, on different days, how good your counterpoise is. Ask around: your boat may be in a bit of an rf black hole (e.g. St. Pete''s marina has this reputation; so does Satellite Beach near the USAF base); adjust its location when doing this, if you need to. Only after you''ve done this initial level of install, consider adding to your counterpoise.
5. People often confuse rf ground (counterpoise) with 12V negative ground, thinking they are essentially the same. This can lead not only to rf running all over the boat''s electrical system, squirting out in funny places, but it can seriously degrade your transmit or receive ability. I recently helped 2 boats fix huge problems caused by them diligently tying these two systems together thoroughly. That''s why I caution you to stay clear of using the engine, metal tanks (which are most likely grounded), etc., at least initially.
Good luck! You''ll no doubt find SSB adding immeasureably to your boating pleasure; the effort is worth it.