Ground question, motor or thru hull?

[Soft Air]

I am testing my new Icom 756pro radio and it seems to be working just fine, I am wondering what is the best ground for it:

Motor or Thru hull?

Thanks

[S/V Illusion]

Lots of stuff in previous discussions - bottom line is there is no single "right" answer but lots of opinions. I infer you mean counterpoise rather than a DC "ground"?

[Soft Air]

Thanks s/v Illusion yes counterpoise.

I will keep on looking on previous threads as well.

[S/V Illusion]

Wasn't sure. There are two schools of though, neither of which is definitively the better. One being to attach the ground side (of the tuner) to a thruhull; the other being a separate copper foil counterpoise. Obviously one is much easier. Some so-called experts have an opinion which is best but frankly, there is no such thing as an expert and in large part, the real answer is a function of numerous variables unique to your boat.

My opinion is try the easy one - a thruhull and see if you are satisfied with it's performance.

Just be careful to not introduce ground loops which can create havoc with other electronics as well as induce or promote electrolysis.

[Soft Air]

Thanks again s/v Illusion, I will do the thru hull solution, I am taking a wire from the SSB straight to any part of the nearest thru hull is that OK?

Right now the wire is going to the engine, what do you think of that?

JC

[S/V Illusion]

Ideally, what you want is an RF counterpoise isolated from the boat's DC ground -it could be argued that it's all interconnected regardless but not necessarily if your thruhulls are not bonded to the engine. In other words, the RF counterpoise and the boat's DC ground should be separate. Many don't bother and it works fine for them.

Potential issues with a common ground/counterpoise are stray RF getting into electronics (more likely than usual), induced electrolysis and noise on the radio.

Consequently, in the long run, you may be better served to connect the radio ground to the DC ground bus and the tuner to the thruhull. This may seem counter-intuitive as they are all electrically connected someplace but there are sound reasons for
physically separating them.

[Nauticatarcher]

Our Hf ground (counterpoise) is flat copper strap to our mild steel fuel tanks and engine, works well

[btrayfors]

Here are a couple of things which might help:

SSCA Discussion Board • View topic - RF GROUNDS IN THE MARINE ENVIRONMENT

Grounding

Bill

[Beausoleil]

Originally Posted by S/V Illusion

...Some so-called experts have an opinion which is best but frankly, there is no such thing as an expert and in large part, the real answer is a function of numerous variables unique to your boat.

There is too such a thing as an expert! The definition is "a has-been under pressure."

That's "ex" "spurt" for the humor impaired.

[Celestialsailor]

Originally Posted by Soft Air

Thanks again s/v Illusion, I will do the thru hull solution, I am taking a wire from the SSB straight to any part of the nearest thru hull is that OK?

Right now the wire is going to the engine, what do you think of that?

JC

I would not use a wire Soft but rather a 2+" wide copper strap. SV Illusion has made some great points