SSB Radio Installation: Need for Counterpoise and additional ground?

[Frix]

Dear Community,

as a total HF noob, I would like to install a SSB system on my Lagoon 400 (good start, I know... But I guess you grow with your tasks).

My system consists of the following basic components:

Icom 802 tranceiver
AT-140 ATU
KISS / SSB
Whip Antenna

All seems to be figured out but one thing:

Everybody seems to write, that you need either a ground (to a metal surface below water line) or a counterpoise (copper foil, KISS, copper paint or whatever).

As I use the KISS / SSB I decided for the counterpoise option. Question: Do I still need to hook the AT-140 to a "real" ground for DC safety? If yes, would I use the same wing nut at the ATU that is connected to the KISS?

I found one skipper, who actually had an outboard ground as well as a counterpoise hooked to his ATU, I just wanted to understand if this was necessary standard or just some specialty.

As always, thank you so much for your replies!

Kind regards and fair winds,
Frix

[carstenb]

The KISS instruction book specifically says "use no other ground". This is the way I have hooked my ICOM802/AT140 up

[AnchorageGuy]

Frix, we use the Kiss on our trawler with a 23 foot antenna. It worked great for us with only the Kiss. I did experiment and added a strap from the tuner to a single thru-hull and it did seem to improve the radios performance a little. I have installed many Icoms on both sail and power. We had the same performance on the trawler with only the Kiss as we had on our sailboat with straps to the Dynaplate, copper screen inside the hull, tanks, etc. Try it for a while with just the Kiss and then try a strap to a thru-hull to see if you get better performance. Chuck

[ka4wja]

Frix,
While I am a proponent of a direct sea water connection RF ground / Antenna ground (and they do work well), the fact is that having any RF ground/antenna ground/counterpoise at all isn't an absolute necessity....
It is all a matter of degree....how much performance do you need/require vs. how much time/effort/money do you wish to spend...

See some specifics in red...

Originally Posted by Frix

My system consists of the following basic components:

Icom 802 tranceiver
AT-140 ATU
KISS / SSB
Whip Antenna

Everybody seems to write, that you need either a ground (to a metal surface below water line) or a counterpoise (copper foil, KISS, copper paint or whatever).
As I use the KISS / SSB I decided for the counterpoise option.

Question: Do I still need to hook the AT-140 to a "real" ground for DC safety?
No, no "safety ground" connection is necessary here...

If yes, would I use the same wing nut at the ATU that is connected to the KISS?
Although, should you desire to improve your antenna system's rf ground, then you would connect other grounding (copper straps from a thru-hull or Dynaplate, and/or additional radials, and/or straps from lifelines, toerails, rails, etc..), to the same ground lug...


I found one skipper, who actually had an outboard ground as well as a counterpoise hooked to his ATU, I just wanted to understand if this was necessary standard or just some specialty.
Necessary, no....
Recommended, usually yes...

To reiterate the facts that I've written before, ANY rf ground/antenna ground/counterpoise is better than none at all.....but even not having one at all, still works....
It is all a matter of degree....


As for whether you can connect other grounding devices, wires, radials, counterpoises, ground straps, Dynaplates, etc. to your tuner's ground lug along with the KISS...
YES, you can!!
(as long as you do not connect your 12vdc negative system to your AT-140's ground lug, which can introduce RF into your DC power system, you're fine...)



I hope this helps...

Fair winds...

John
s/v Annie Laurie


P.S. If you wish to read some details about the KISS SSB-Ground, please have a look here..
SSCA Forum • View topic - KISS-SSB Counterpoise

[Frix]

Dear Community, thank you very much for your valuable answers.

This helped a lot. So now I understand, that all the HF-grounding / counterpoising connects to the "ground lug" at the ATU. This only aims at building a good "antenna system".

I also learned, that there is no need for "safety grounding" as known from AC installations since DC is grounded via the negative anyways (which I - being the land dweller with only a bit of 220 V AC know how- simply wasn't aware of).

Thanks again for pointing me into the right direction.

Fair winds, Frix

[AnchorageGuy]

Frix, Here is a blog post we did on the installation on our trawler. Yours would be very similar. Hope it helps. The Trawler Beach House: Is It Hard To Install A Single Side Band Radio?
Chuck

[ka4wja]

Frix,
You're welcome!

Be sure to get on-the-air and test everything before you head out offshore...

Fair winds...

John
s/v Annie Laurie