Grounding Plate for SSB

[SV Bacchus]

Hi All,

About to close on a new to us Leopard 42. The boat has, according to the surveyor, a top-notch install of a SSB. I don't have the paperwork with me but I believe it is an Icom 802.

Uh, With the exception of grounding. He showed me the 3 or 4 inch wide strip of copper grounding going down into a bilge in the starboard hull. Then the copper is just laying there, 2 or 3 folds back and forth on top of each other. He said it would work, huh???? But he added the true ground to get max performance of the radio is a grounding plate outside the hull, on the bottom. He described it as a plate maybe 6"X12" and looking like a mass of copper BB's welded together explaining that gives the small footprint maximum water exposure.

He didn't know the name of a manufacturer or didn't want to get in the business of making vendor recommendations. At any rate, I don't know who or where to get one. He suggested I add it to my next "haul out list" so I wouldn't forget it.

1) Can anyone tell me good or best maker and where to buy?

and

2) Mounted to the hull with bronze thru bolts to facilitate connections inside?

and

3) Mounted first then new antifoul or do the antifoul first then mount the plate?

[MYTraveler]

This: Super Dynaplate used for SSB radio | Marinco

Don't paint it (it will last for ever, but not work very well, if you do).

[SV Bacchus]

Originally Posted by MYTraveler

This: Super Dynaplate used for SSB radio | Marinco

Don't paint it (it will last for ever, but not work very well, if you do).

I like it! Thanks much!

I knew I could Google it but I was looking for recommendations from those with experience.

[Jim Cate]

Originally Posted by SV Bacchus

I like it! Thanks much!

I knew I could Google it but I was looking for recommendations from those with experience.

those with experience say it is not necessary at all!

See the MANY posts on the subject, especially those of KA4WJA. John has repeatedly advised on the subject.

Jim

[a64pilot]

You don’t need a dynaplate,
IF and only IF you have a thru hull or other metal that penetrates the hull in close proximity to the tuner. In my case I didn’t which meant that I would have to locate the tuner close to a thru hull, which would make the RF output wire from the tuner too long, so I had a dynaplate installed as close to where I was going to mount the tuner as possible, keeping the ground connection and the GTO 15 connection relatively short.

The idea is if possible to get a direct connection to the water your floating in. From reading it seems that you want to keep the metal foil as short as possible, up to 10 feet is acceptable.
Many people have run a counterpoise as opposed to a ground.
On my boat the rub rail is a preferred way, but I’m led to believe that the best is a short connection to the Ocean your floating in, with copper strap.

[Dsanduril]

I'm with Jim and John, you don't need any hull penetration or connection to salt water. Copper foil and/or screen laid out in the bilge forms a capacitive connection with the water providing an RF 'ground' (counterpoise). You do need to use wide foil to the bilge, it has a very low inductance at HF frequencies compared with wire (even a very large wire). In the bilge you lay out as much foil or screen as you can (some guides recommend 100 square feet/10 square meters!). I like to lay out the ground plane then epoxy it into the bilge to stop the copper from rotting if (when) it gets wet. If you don't have room in the bilge/can't access the bilge/don't want to go to the trouble then a Dynaplate will work (probably just fine) but my preference is a capacitive RF foil ground - YMMV.

Been doing it that way for a long (very long) time and have always had a strong (and quiet) signal.

[Cheechako]

I used copper foil glued in the transom. It was not on the hull where the water was outside. I had killer signal according to everyone. People would rely on me for the weather net interaction. I dont think a plate bolted thru the hull is necessary at all.

[S/V Illusion]

Originally Posted by SV Bacchus

Hi All,

About to close on a new to us Leopard 42. The boat has, according to the surveyor, a top-notch install of a SSB. I don't have the paperwork with me but I believe it is an Icom 802.

Uh, With the exception of grounding. He showed me the 3 or 4 inch wide strip of copper grounding going down into a bilge in the starboard hull. Then the copper is just laying there, 2 or 3 folds back and forth on top of each other. He said it would work, huh???? But he added the true ground to get max performance of the radio is a grounding plate outside the hull, on the bottom. He described it as a plate maybe 6"X12" and looking like a mass of copper BB's welded together explaining that gives the small footprint maximum water exposure.

He didn't know the name of a manufacturer or didn't want to get in the business of making vendor recommendations. At any rate, I don't know who or where to get one. He suggested I add it to my next "haul out list" so I wouldn't forget it.

1) Can anyone tell me good or best maker and where to buy?

and

2) Mounted to the hull with bronze thru bolts to facilitate connections inside?

and

3) Mounted first then new antifoul or do the antifoul first then mount the plate?

As others have said, dynaplates are unnecessary as an RF counterpoise.

If your surveyor told you otherwise, it means only that he should stick to what he knows.

[a64pilot]

As your hearing, from what little I can find out, most anything works, some better than others and as it’s not possible really to directly compare one method to another there are differing opinions.
Some swear by the KISS counterpoise, while I have read from people that know what they are doing that it’s not worth what it costs, you can knock out something similar for very little money.
I’m in the middle of installing my SSB so I’ve tried researching as much as I can.
It probably really does not compare, but in my mind a counterpoise is similar to a ground plane, and if so the Ocean is a pretty large ground plane.
I believe Dynaplates are the accepted, old school way. Person I bought mine from connected to the large metal piece in his lifting keel, giving him a direct connection to the water, without having a plate to clean.
However oddly so far my plate is as clean as a whistle, but it’s mounted under the boat on my full keel and is always in the shade, maybe being in the shade is why it hasn’t gotten any growth yet.
I also have it on good authority that the sintered metal a Dynaplate is made from is of no advantage over just a simple flat plate. Maybe the “made from thousands of BB’s” is a marketing thing?

[model 10]

What is the resistance of marine growth? All the little passages in a Dynaplate fill up with it. A bare copper plate is covered with it in no time

[Frankly]

The Dynaplate now on A64's yacht used to be on my aft keel and an equal size solid copper plate fwd beside the mast step (lightning ground). Both on the port side in the shade. Both collected hard and soft growth about the same but the smooth copper plate is a little easier to scrape. Found that the SS tube housing the centerboard cable would work just fine for a HF SSB ground so off came the DP. One less thing to scrape.

Don't let anybody tell you that pure copper won't foul, "taint so".

[SV Bacchus]

Now everyone has made me a happy man! I didn't want to drill a hole for a bolt and it seems the wide copper foil running down into my bilge is sufficient.

Thanks all, it is most appreciated!

PS: I'm approaching this new to me boat from the angle of don't change anything until I've tried it for 6 months. I was only going to do this now as I wanted to do it during haul out for anti-fouling. Glad I asked the question and now won't touch it.

[sck5]

try using the ssb. If you can talk to people they can tell you the quality of your signal. If you are unfamiliar with SSB's you might want to get somebody with some experience to help. It isnt always as easy as a VHF.

For what its worth I have had dynaplates on two boats. They worked great. A wire brush, a mask and snorkel were all the equipment I needed to keep it clean. Didnt even need that very often. DONT PAINT IT or you will defeat the purpose. But there are other solutions as you see above. Some people have religion about this topic but the real test is whether or not you can talk to people. If yes, then leave it like it is. If not, try to improve the counterpoise or install a dynaplate.

[SV Bacchus]

Thanks sck5!

To all: I was never going to paint the dynaplate. My question should have been a little clearer. Paint the hull first then install or install the plate then paint AROUND it? Now I know I'm not installing, at least not until I know I need to do so.

Thanks again everyone!

[SV Bacchus]

The copper foil in the bilge, I had forgotten it was mounted around vertical walls of the bilge and then the excess was laid in the bottom.