SSB ground plate

Mar 28, 2020
11
Payout Lusaine New Havem
I am thinking of adding a ssb radio.
i am a weekend coastal sailor.
the ssb would be for something interesting to have.
I would not de a serious user.
I have no metal through hulls. And have an outboard motor.
the question is about a ground plate.
i would have a removable 1ft sq copper plate to put in the water when using the radio.
the antenna would be a long whip style.
comments on the ground plate ???
Thanks. Nick
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
Nick, moving you over to the SSB/Ham side of the forums.

Based on your question, either you just want to play on Marine Band frequencies (assuming you have a license to do that) or you want to play on the Ham Band (and... assuming you have a license to do that).

You have several options. Although you said you have no "metal" thru-hulls, you can certainly add on (if you wanted) Seawater is an excellent counterpoise for HF SSB radio. Sure, you can drop a plate over the side (or aft) for your seawater counterpoise. You can also install a through bolt that is attached to the ground of you antenna tuner.

Next option is this thing called a KISSsb. The are pricey but you can build your own. I use a DIY KISS at home on my 106.5' long wire. Works just fine and I get out well. Not attracting any DX signals but meh, I am not into that anymore.

Another solution is to ditch the vertical whip and go with a vertical dipole. No tuner needed, no ground needed. The con being it is only a single band antenna. You have to have to real estate from the stern to the top of the mast to support it. But this is a drop dead easy solution.

You can also use the toe rail, or the lifelines, or anything that is contiguous and not bonded to ship ground. The reason I recommend staying away from sharing ships ground is radio wave are and AC component. Mix AC with DC and that could cause bad corrosion somewhere. If you do go that route, bypass capacitors would be beneficial.
 
Mar 28, 2020
11
Payout Lusaine New Havem
Nick, moving you over to the SSB/Ham side of the forums.

Based on your question, either you just want to play on Marine Band frequencies (assuming you have a license to do that) or you want to play on the Ham Band (and... assuming you have a license to do that).

You have several options. Although you said you have no "metal" thru-hulls, you can certainly add on (if you wanted) Seawater is an excellent counterpoise for HF SSB radio. Sure, you can drop a plate over the side (or aft) for your seawater counterpoise. You can also install a through bolt that is attached to the ground of you antenna tuner.

Next option is this thing called a KISSsb. The are pricey but you can build your own. I use a DIY KISS at home on my 106.5' long wire. Works just fine and I get out well. Not attracting any DX signals but meh, I am not into that anymore.

Another solution is to ditch the vertical whip and go with a vertical dipole. No tuner needed, no ground needed. The con being it is only a single band antenna. You have to have to real estate from the stern to the top of the mast to support it. But this is a drop dead easy solution.

You can also use the toe rail, or the lifelines, or anything that is contiguous and not bonded to ship ground. The reason I recommend staying away from sharing ships ground is radio wave are and AC component. Mix AC with DC and that could cause bad corrosion somewhere. If you do go that route, bypass capacitors would be beneficial.
Brian. I have about 60ft of lifeline. Two rows at 30ft ea. on the same side of the boat.
Would this make a suitadle ground ??
Thanks. Nick
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
Yes, it could be used as a counterpoise for your antenna. One thing you have not done is tell us what kind of boat, what kind of radio, does it have a tuner, what kind of whip, etc? Without this information all we can do is give rudimentary suggestions.
 
Mar 28, 2020
11
Payout Lusaine New Havem
Yes, it could be used as a counterpoise for your antenna. One thing you have not done is tell us what kind of boat, what kind of radio, does it have a tuner, what kind of whip, etc? Without this information all we can do is give rudimentary suggestions.
The boat is a 37ft cat. As for the rest it’s all very preliminary.
Don’t want to cut rigging.
Thought about sliding a insul copper wire up a shroud for the antenna, perhaps in a small plastic tide. Design pending. Are antennas dangerous when transmitting? I like diy.
Thanks again for your reply’s.
Nick
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
They can be if one touches the antenna wire during transmission. The maximum current is at the base of the antenna.

A wire up the mast as you mentioned is called an "alternative backstay antenna". They are usually around 43 feet in length. That length includes the feed wire (GTO15) from the tuner to the base of the antenna. So the whole antenna length is from the base of the tuner to the top of the mast. The minimum recommend length is 23 feet. However, any length will work with today's modern automatic antenna tuners.

The antenna wire can be vinyl coated stainless steel wire rope. Nix the copper, it will not last in that environment. The SS is basically the same as lifeline wire rope. Using a spare halyard, one runs the wire rope to the top of the mast (less 2 feet). It is then tied down to the transom where the GTO15 feed exits the hull. It is then connected to the wire rope and voila, you have an antenna system that you can take down.

On my signature in this and other posts you will find my website. There you can review several papers on working maritime mobile. It is worth the read.

Oh and I should welcome you to SBO. Sorry about that. I seldom look to see how many post a user has.
 
Mar 28, 2020
11
Payout Lusaine New Havem
They can be if one touches the antenna wire during transmission. The maximum current is at the base of the antenna.

A wire up the mast as you mentioned is called an "alternative backstay antenna". They are usually around 43 feet in length. That length includes the feed wire (GTO15) from the tuner to the base of the antenna. So the whole antenna length is from the base of the tuner to the top of the mast. The minimum recommend length is 23 feet. However, any length will work with today's modern automatic antenna tuners.

The antenna wire can be vinyl coated stainless steel wire rope. Nix the copper, it will not last in that environment. The SS is basically the same as lifeline wire rope. Using a spare halyard, one runs the wire rope to the top of the mast (less 2 feet). It is then tied down to the transom where the GTO15 feed exits the hull. It is then connected to the wire rope and voila, you have an antenna system that you can take down.

On my signature in this and other posts you will find my website. There you can review several papers on working maritime mobile. It is worth the read.

Oh and I should welcome you to SBO. Sorry about that. I seldom look to see how many post a user has.
Brian. One last question.
what size wire would you use from the tuner or the radio. Possible run of 20’+/-
thanks again for all your advice !!! Nick
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
I use RG8X since we are dealing with HF (3-30MHz). But if you want less loss (and there really isn't much loss) you can go with Times Microwave LMR-240.

RG8X - 20' - - 14MHz -.2dB loss
LMR2400 - 20' - 14MHz - .1dB loss

I know you will have more questions, no worries.
 
Mar 28, 2020
11
Payout Lusaine New Havem
I use RG8X since we are dealing with HF (3-30MHz). But if you want less loss (and there really isn't much loss) you can go with Times Microwave LMR-240.

RG8X - 20' - - 14MHz -.2dB loss
LMR2400 - 20' - 14MHz - .1dB loss

I know you will have more questions, no worries.
Thanks again. Have much to ponder. Nick