SSB radio antenna grounding

[Stranizza]

I am in the process to install an SSB radio and I ear different opinions and suggestion how to ground the antenna in an alluminum hull, goes from connect directly to the hull , conect to the engine, paint with a special paint 3 square mt of the internal hull ...as the more credible one...I am not going to mention the more eccentric.
Is any of you can share what kind of grounding has in the own boat and if discover any type of problem related.

Thanks & Rgds

Angelo

[Dummy]

Hello Angelo & welcome to the OVNIClub !

I don't know if you can understand this thread : http://www.ovniclub.com/forum/blu-masse-t119.html by using Babelfish or the Google translator ? it answers most of your questions.

In summary the way most SSB radios are mounted on Ovni yachts : the AT box is grounded /connected to the hull through a "high capacity" condenser or capacitor, which blocks DC current (hence preventing potential electrolysis issues), but not the AC current (HF in this case) so the radio and antenna work. Sometimes several capacitors are actually used, as they also function as filters.

The AT box reads for Automatic Antenna Tuner (e.g. AT 130 or 140 if you are using an ICOM SSB) and really helpful, especially if you are using an isolated backstay as the antenna. This AT box should be located as close as possible to the antenna.

This of course is valid for an Ovni aluminum boat (and most pleasure alu sailing boats in France whose hulls are totally isolated) using a bipolar electrical scheme. In this case the other solutions you quoted would be detrimental. However pls. note that not all aluminum boats have the same type of electrical system. As for some professionnal alu. boats (a legal requirement in some activities/countries) the hull is grounded and some of the solutions you listed may work.

Hope this helps.
Best wishes, Kevin

[Careka]

here is a picture from S/Y Oda norwegian 395 with the SSB antenna for backstay