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Old 24-09-2020, 22:58   #1
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SSB ground to a copper strap?

I’m sure this has been dealt with somewhere, but I couldn’t find it.

Contrary to the good advice here, this spring I was running out of time with many projects and purchased a KISS SSB ground before setting off cruising. Not sure about transmission, but reception was about the same with it or without it as John (ka4wja) and others assured me it would be.

Anyway, I will now install a copper strap between the tuner and a seacock, about 3-4 feet apart. My question is how do I attach the strap?

I have read that the strap should be “clamped” to the seacock. Not sure what that means, but wouldn’t it be better to drill holes at each end of the strap and fix one end to the screw at the tuner ground and one on the seacock normally used to ground DC circuits?

Advice appreciated.
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Old 24-09-2020, 23:30   #2
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Re: SSB ground to a copper strap?

foojin,
This is a good way to do it....and is the recommended way by many...
So, go for it!
Quote:
Originally Posted by foojin View Post
I will now install a copper strap between the tuner and a seacock, about 3-4 feet apart. My question is how do I attach the strap?

I have read that the strap should be “clamped” to the seacock. Not sure what that means, but wouldn’t it be better to drill holes at each end of the strap and fix one end to the screw at the tuner ground and one on the seacock normally used to ground DC circuits?
BTW, this is how I attach my copper strapping to both my tuner ground lug, and to my Dynaplate bolts...



Depending on the width of the strapping (and its thickness), you will usually want to either fold it into a blunt point, or cut it to a blunt point, to allow easier fitting / attachment....


And, only drill the hole after you've bent / shaped the strap as needed (and either cut or folded the ends to make fitting/attachment easier)....and only drill the exact sized hole needed....and use of bronze washers on the seacock bolt is good....(SS washers on the tuner ground lug are fine)


Make the contact flat/smooth and CLEAN, and apply a small amount of Penetrox-A and tighten the connection...make it tight! Really TIGHT!
Then, slop a dollop or two of Penetrox-A onto the outside of connections, and you'll be good for many years!



Although, certainly not a requirement, I always recommend using some Penatrox-A conductive grease (the opposite of tef-gel), on the seacock-to-copper strap connection....this will keep the connection clean and free of corrosion for quite a while....use it on all parts of the connection, threads, washers, bolts, nuts, studs, etc....and then a dollop or two on top, to keep it all clean and dry, and low-resistance!
(and, yes, I also do this on my own boat.....and have been using this stuff for decades....it's wicked messy and can stain clothing, but it works! and, while it ain't cheap, it just takes a dollop, and it lasts a long time!)




Fair winds.

John
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Old 25-09-2020, 08:20   #3
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Re: SSB ground to a copper strap?

If you have a KISS counterpoise, why are you adding a copper ground strap?

We have KISS counterpoise and have found good-to-excellent transmission on both HAM and marine SSB HF frequencies. We regularly converse (during our Summer cruises) with other boats who also have the KISS systdm... they boom in.
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Old 25-09-2020, 08:43   #4
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Re: SSB ground to a copper strap?

Oh goodness....please let's not go 'round 'n round on the KISS again.
There are already threads discussing this endlessly, perhaps perusal and queries there would be better?


But, in brief....
This is all a matter of degree!

---- ANYTHING metallic can be used as an HF antenna and/or an HF antenna ground....it's all a matter of degree of how well it works...

---- And, while anything metallic can be used as an HF antenna ground, even nothing at all works! (yes, you can make plenty of contacts, many with strong signals, with NO antenna ground at all!)


All of this (HF communications) is about received signal-to-noise ration (S/N), and how best to obtain the highest rec S/N....(which means learning about radiowave propagation, antenna system design / choice / construction, and actual HF radio operations...)

And, all regarding antenna, and especially antenna ground systems, is all a matter of degree!


{although it's not a certainty, chances are good that you'd find little to no change at all in your HF comms performance when disconnecting the KISS completely....just saying, this is all a matter of degree, and in most (all?) situations where a KISS is installed, owners find little to no effect disconnecting it....makes you go "hmmm?", doesn't it?
btw....don't worry if this all seems weird, too good to be true, against what is marketed, etc....because it is! but, it is also 100% true....in addition to the lab and scientific studies/tests, I've been on-board doing this (HF radio installs and HF radio operating) on offshore boats now for about 45 years....(I assisted in my first marine HF/SSB install in 1973)...}


BTW, if you are interested, as has been written about here many times (and both lab tests published and real-world tests results published as well), you can make your own "KISS" ground that actually works better than the one being sold for $150, for just about free! (or at most $5)


Of course, if you are actually interested in optimizing your HF comm system, you're not going to be messing with anything like this....
Instead, you use the sea water you're floating in, and make a short, low-impedance connection to the sea water....and, you'll have one of the best overall, wideband HF antenna grounds there is...(of course, nothing is perfect, and certainly not on-board our boats....but, this is the best approach for those in salt water )



Fair winds

And please if you wish to discuss the KISS further, have a look at the stickies above, read thru them, and all the other threads regarding the dispelled myths of HF antenna grounds, the KISS, etc....
And then, if you still have some questions, post them on a KISS thread or start a new thread of your own about it...

John
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Old 25-09-2020, 08:47   #5
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Re: SSB ground to a copper strap?

Quote:
Originally Posted by foojin View Post
I’m sure this has been dealt with somewhere, but I couldn’t find it.

Contrary to the good advice here, this spring I was running out of time with many projects and purchased a KISS SSB ground before setting off cruising. Not sure about transmission, but reception was about the same with it or without it as John (ka4wja) and others assured me it would be.

Anyway, I will now install a copper strap between the tuner and a seacock, about 3-4 feet apart. My question is how do I attach the strap?

I have read that the strap should be “clamped” to the seacock. Not sure what that means, but wouldn’t it be better to drill holes at each end of the strap and fix one end to the screw at the tuner ground and one on the seacock normally used to ground DC circuits?

Advice appreciated.
Many seacocks have a tapped small hole in the flange to attach a bonding wire. Does yours? Simply solder a good size wire to your copper strip and attach the wire to your seacock somehow.
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Old 25-09-2020, 09:42   #6
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Re: SSB ground to a copper strap?

Oh, I certainly already read all the posts over the years as well as other related articles (eg Gord May's seawater ground), both before and after we got the KISS. Fully aware of the "round & round" re KISS.


No intention of restarting it. Just info for OP.
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Old 25-09-2020, 09:43   #7
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Re: SSB ground to a copper strap?

Since HF travels on the surface of a conductor many favor using tinned copper braid to make ground connections.
If it's difficult to connect your copper strap to the seacock you could use braid as is shown in this automotive example.
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Old 25-09-2020, 10:02   #8
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Re: SSB ground to a copper strap?

Would like to chime in with a few questions please. Everything I've read about attaching copper strapping to a seacock suggests "clamping" them together with hose clamps. Thinking that through, I'm still interested in an answer to foojin's original question above...how do you physically clamp the end of a strap to a seacock? (Perhaps slots need to be cut in the copper so the hose clamp(s) can encircle the connection completely?) And as I understand it, ground strapping is all about surface area...is this not defeated if a wire connection is employed at the seacock end?
I'm also wondering if a copper strap run flat against an underwater water or fuel tank can utilize the large area of the tank to connect with seawater through capacitance?
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Old 25-09-2020, 10:32   #9
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Re: SSB ground to a copper strap?

I know this thread is focused on grounding to a seacock but if you have one you should also consider grounding to an external keel.

An external keel provides much more surface area to act as a seawater interface. If you have one and can get to a keel bolt that is a much better way to go. That is how I set up my boat. I have Marelon seacocks so that is not even an option.

When providing a counterpoise the most important ground connection is from the antenna tuner, not the radio. Flat copper is essential but avoid the super thin stuff you buy at marine stores - they charge more for less. Surface area matters but being thin does not matter and is counter productive. Thin copper rots out quicker and then needs to be replaced. Flat braid is both not wide enough and will not last in a marine environment.
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Old 25-09-2020, 10:47   #10
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Re: SSB ground to a copper strap?

guyrj,
Unsecured "braid" whether bare copper, tinned copper, or stainless-steel, is never recommended for RF grounding, never ever...("braid" inside coax is different...as it is secured)
Heck, even "stranded-wire" is not regularly used, and never recommended....solid wire, or strap....
(and the RF world has been this way since the days of Marconi, WWI era....and while definitive engineering of all this didn't come along until the 1920's and 1930's, from RCA, GE, Westinghouse, etc....and of course Bell Labs / ATT&T....and then post WWII, in addition to the continuation of all those above, we have the likes of Motorola, GE, Bell systems, HP, NEC, etc. etc...the facts are that "braid" is never, recommended in RF...)

Quote:
Originally Posted by guyrj33 View Post
Since HF travels on the surface of a conductor many favor using tinned copper braid to make ground connections.
If it's difficult to connect your copper strap to the seacock you could use braid as is shown in this automotive example.
For DC grounding, braid can be used where flexing is required, but even in DC grounding (and low-freq AC grounding) braid is not usually recommended....

Now unfortunately , I understand that "some" do use braid in RF environs....heck, I've even seen RF products produced for sale that used braid, but any RF engineer simply shakes their head in disbelief.

Yes, RF does travel on the skin of a conductor, and the "skin-depth" depends on the frequency and type of conductor (copper, SS, salt water, etc.)....

And, this is exactly why braid is NOT a good choice...
a) as the small distances of separation between the tiny wires of the braid increase the RF impedance of the connection (the opposite of what someone is trying to accomplish when using a wide, large surface area conductor)
b) the "semi-conduction" between these unsecured braid wires, can rectify the RF and cause oh so many issues in transmit!! (very, very bad....but, again, I have personally seen some "CB Radio amplifiers" built with tinned or even silver-plated copper braid! Agh!)
c) the constant "making" and "breaking" of these small wires of the braid can (even if using "tinned" or "stainless" braid), they can cause excessive receive noise, in both your HF system, as well as cause interference in/on other systems on-board...


guyrj, the list goes on and on....

But, the gist is: I take issue with your words "many favor using tinned copper braid to make ground connections"....
Because in the world of RF (Radio Frequency), "many" actually do not!

Yes, as I wrote, unfortunately some folks do use "braid"....but, this is wholly and completely against all good engineering and against all professional recommendation!

Yes, I see this use of "braid"....and I wonder why?
Why?
Really, why?
It's usually more expensive and always a bad choice for RF...so, why do people use it?
The only answer I've ever gotten is: "that's what I read somewhere", or "that's what I was taught, or told", or "that's what this 'professional' does", etc. etc...(but, nobody ever actually learns the reasons why this is a bad idea)



Please excuse the above words, if they seem like a rant...that's not my intention...
But, foojin asked if his assumption on how best to attach his copper strap was a sound idea (it is, btw), and he gets comments suggesting he use a KISS Ground, and now someone recommending copper braid?
And, it seems that while these are both polite and well-intentioned, they are rather poor engineering choices...and, that is what I'm trying to point out!

Of course, everyone is entitled to their own opinions and everyone is welcome to share them here...
I'm just pointing out some facts that everyone can use...





BTW, in regards to using keel bolts....yes, they can be a good option...but...
But, usually they are such a far distance from the tuner (more than 8 feet is "far"), that the flat strap is acting as much of the antenna ground as the sea water....and if the distance is ~ 15' or more (as it is on m boat), you can be almost certain that it is the strap that actually is your antenna ground, not the sea water....(hence the reason I have Dymaplates....as I also have all Marelon thru-hulls)


{btw, in full disclosure, I have two 18" x 6" Dynaplates, attached to two runs of 6" wide copper strapping, about 6' long....AND from there-on forward, I have a 3" wide copper strap, of approx 15' long (> 20' from the tuner), from the Dynaplates, forward to a keel-bolt (9700 lbs. ext. lead keel)....AND, I also have a short (12") run of 3" copper strap, running to two large flat aluminum tanks (approx 30 sq ft of surface area, within 1/2" of hull)....so....
So yeah, I am a fanatic when it comes to electronics / communications....but, I admit it!! (and, I've made my living in this business for many decades, so, if I don't know what I'm doing by now, I'd be a fool! LOL ) }


















Fair winds.

John
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Old 25-09-2020, 11:16   #11
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Re: SSB ground to a copper strap?

Quote:
Originally Posted by ka4wja View Post
This is a good way to do it....and is the recommended way by many...
So, go for it!
Thanks for the confirmation, John. Many thanks.

Another question if I might. I have found little information about grounding the radio (rather than the antenna). Can this be done by copper wire to a seacock? I have read, not sure, maybe in your posts, that the radio and antenna grounds should never touch each other, but even if I connected the radio ground to another seacock would they not be connected through the water... or am I overthinking it?
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Old 25-09-2020, 11:39   #12
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Re: SSB ground to a copper strap?

Quote:
Originally Posted by foojin View Post
Thanks for the confirmation, John. Many thanks.

Another question if I might. I have found little information about grounding the radio (rather than the antenna). Can this be done by copper wire to a seacock? I have read, not sure, maybe in your posts, that the radio and antenna grounds should never touch each other, but even if I connected the radio ground to another seacock would they not be connected through the water... or am I overthinking it?
The radio and the antenna tuner are grounded together through the coax cable.
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Old 25-09-2020, 11:51   #13
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Re: SSB ground to a copper strap?

Quote:
Originally Posted by Poeme View Post
Would like to chime in with a few questions please. Everything I've read about attaching copper strapping to a seacock suggests "clamping" them together with hose clamps. Thinking that through, I'm still interested in an answer to foojin's original question above...how do you physically clamp the end of a strap to a seacock? (Perhaps slots need to be cut in the copper so the hose clamp(s) can encircle the connection completely?) And as I understand it, ground strapping is all about surface area...is this not defeated if a wire connection is employed at the seacock end?
I'm also wondering if a copper strap run flat against an underwater water or fuel tank can utilize the large area of the tank to connect with seawater through capacitance?

A short wire, which will only have to be a couple inches at most, will not noticeably increase the impedance of the ground connection. Keep it short and use largest size wire that works. With RF the combination of length and surface area is what counts.
Capacitance can provide a partial ground to seawater. More so at higher frequencies. It takes a large area to make a difference, depending on thickness of your hull, and the metal must be in close contact with the hull. Especially at lower frequencies, it's more likely that the metal tank or for that matter any internal-only ground system functions mainly by means of direct RF coupling to the antenna rather than functioning to extend the ground to the seawater.
But if you can bond the copper strap, plates, what have you, directly to the hull and eliminate air gaps as much as possible, there can be effective capacitive coupling if the area is large enough.

If you want to connect to a metal tank, it may be best to make a direct connection to it. Don't just lay the strap on the tank. Connect to the tank at any metal fitting such as the vent or the fill.

BTW marine outets carry a "copper strap" material for SSB grounds, but it is very thin and fragile IMHO. I got some thicker copper strap from a local metal supplier and it has held up well.
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Old 25-09-2020, 12:56   #14
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Re: SSB ground to a copper strap?

Poeme, et al,

Well....I hadn't planned on going thru all of this here again....(this is all covered in the stickies above, and the links provided there!)

But, in brief...

1) The recommendation to "clamp" copper strapping to a thru-hull, is (in my opinion) a confluence of two things...LOL

a) one, was the use of an underwater bronze thru-hull as means of direct sea-water connection...(although today with a good deal of Marelon and unfortunately many cheap brass thru-hulls, this is not always useful advice, anymore...)

b) the other part of the confluence is, the old (very poor) recommendation to use "copper foil" as the ground connection "wire"....rather than thicker "strapping" (and, of course, in those old recommendations, few mentioned the need to properly secure/clamp these connections, and certainly little, to no, mention of protecting these connections)


Back when we had people erroneously recommending thin copper foil (unfortunately I think Gordon West still uses his 20+ year-old script, where he says "foil"), which is usually only 0.001" to 0.003" thick, it was easy-peasy to just warp this around the sea-cock and secure with a hose-clamp...just like wrapping a potato in aluminum foil, but who here would think if you did that, and threw that foil-wrapped potato in the bilge, how long would it last down there, rolling around in some sea water??


Now, from an engineering prospective, we all know that this was never a good idea....but, that didn't stop sailors (and the so-called "experts" selling stuff to unsuspecting sailors) from using it / doing this...it was quick-n-dirty, and cheap...but, never a good approach...



And then, we had many bemoaning this approach in a year or so, down the road....as they never protected this connection (nobody ever told them to), and the drips of sea water and other water, etc. in their bilges corroded the thin foil quickly, and of course the hose clamp never gave the foil much of a low-impedance / low-resistance connection (even when new!), and as it corroded and/or loosened, the "connection" was no more!

And, then we had sailors complaining that "that copper foil is useless" (which it ended up being)....

But, instead of going back to the source of these erroneous recommendations, and saying "hey, what the heck are you doing, recommending this? Have you actually seen this stuff in use on-board, after a year or so? When was the last time you went on-board an offshore cruising boat, and actually looked at things, and actually used their radio system?"

Nope...nobody seems to do that....they just assume the idea is crap, and scrap it....and what 'da ya' know, someone comes up with some snake oil (the KISS Ground) that "solves" their problem!

When all that was needed was to use good engineering from the start / all along!


Use thick copper strap (I use 0.022" thick....but most find 0.012" thick to be fine)....and, except for the very end where connections are made, protect it well (paint, epoxy, varnish, duct tape, etc...just use something to protect it)....attach it / connect it properly (using clean, wide / flat connection), bolts or clamps, etc....and protect those connections....and viola, the darn thing works well, and lasts decades!!!


Btw, I did not paint/protect my 6" wide copper strapping, as it is 0.032" thick, and it will last longer than me....but I do apply Penetrox-A on the bolts, studs, washers, nuts, etc...and, I did protect my long 3" wide strapping (clear lacquer along the whole length, and even duct tape along the section that things may contact it when working in bilge)...

All of this info is available for FREE from many sources....
The Sailmail Primer....
SGC....Icom....Furuno....Sailor/Thrane.....JRC....Cruiser's Forum....OCC....etc..
heck even the Motorola RF grounding manual is free on-line!

Again none of this is new....you know, electrons flow the same way today as they did a few years ago, and the same as they did decades ago....physics hasn't changed much in years...and this isn't rocket science!

Now in years/decades past, I also posted all of this info with the SSCA, but a couple years ago they (the SSCA) took all of my info/postings (and everyone else's that so graciously contributed their wealth of knowledge, for free), and the SSCA took all of this from us, and made it all private and available to their members only....so, even though I was a "rear commodore", I thought this was totally against the vision of the SSCA, and I've never looked back....and, btw, I think if you pay the ABYC for access, they have this info as well...

So, I'm sometimes surprised that many of my fellow sailors actually pay money to get erroneous info, or take random advice on high-tech from untrained fellow sailors, rather than getting accurate, factual info for free, from many sources....it's all there for you...




2) BTW, Hinckley and Swan are the only two yacht builders / boat manufacturers, that I've ever seen that properly install HF radios (and an HF radio antenna ground strap / ground system)....

Pardon the digression....but...By happenstance, a few years ago I spotted a Hinckley on a dock in St. Pete, FL....and while the hull had been Awl-gripped a different color, I notice two custom hatches on the cabin top....yep, that was my parent's old Hinckley, which was ~ 45 years old, at that point....

I BS'ed my way onto the dock, and knocked on the hull....when I asked if it was hull number xx, the owners just stood with blank stare and said a quiet "yes?"....I explained that I grew up sailing on that very boat.....they invited me aboard, and we were like long-lost friends in no time....I was able to look at the Nav Station (upgraded with new electronics of course), and when I looked at the Icom HF radio and tuner, I found the same friggin' 6" wide copper strap that I used > 40 years ago (that was installed by Hinckley, when the boat was built > 40 years ago!)!!!
100% true story....

And fyi, I spent some time on a Swan 57, which was a dream....but the wicked-cool 400-500 watt Sailor SSB, and the massive (8" wide, I think) copper strapping....wow....I still remember the owners name "Theo", and he had such a thick German accent, he kept pronouncing his own name as "Te O"....ah, the things you remember....

Again, sorry for the digression!




3) As for the "surface area" situation....again, this is all covered in the links in the stickies....but...

But, two things in brief:
a) the impedance of a conductor (sort of like its resistance at "radio frequencies" / RF) is controlled by its surface area AND its length....a short piece of wire (a couple inches or 12 ga, etc.) will have negligible effect on the ground conductor's impedance...

b) this is not a NASA engineering project....it's a boat, and an HF antenna system...so, compromises can be made, without any major impact on performance!

Please remember, this is all a matter of degree!!





4) And, as for "capacitance-coupled" antenna grounds...again, like all the rest of these questions, this is all covered in detail in the stickies above (look at the top of the Marine Electronics threads, and you'll see them!)...

But, again, in brief:

As has been proven by real-world testing (with instantaneous-switching), and in the lab, and with the "math"....capacitively-coupled HF antenna grounds are very inferior to a direct sea-water connection! (see details in the links in the stickies....the most often used/read info on this is Gordon West's definitive real-world tests from southern California, years ago....but, I and others have done the same, with the same results)

And, yes....here again, there are many unscrupulous folks willing to take your money, and give you both bad advice and useless products....but again, the facts are right there for you, for free!!



I hope this clarify things?

Fair winds...

John

P.S. Again and again, I see many folks asking questions about the exact subject that we put together the "stickies" for....they are generally for reference only, but some do add a comment occasionally and I also add to them when needed, and when I have the time...
But, please understand that they are there for you 24/7/365, for free....and if you follow the many links there, you get all the HF comms info you'll ever need...all for free!
Have a look see!
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Old 25-09-2020, 13:18   #15
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Re: SSB ground to a copper strap?

Whoa there guys!!!
I cannot type fast enough....please take a breath!!!



Again....again, the answers are there in the stickies!
I will give you the brief / quick version here, and then I'm done!!!
Quote:
Originally Posted by foojin View Post
Another question if I might. I have found little information about grounding the radio (rather than the antenna). Can this be done by copper wire to a seacock? I have read, not sure, maybe in your posts, that the radio and antenna grounds should never touch each other, but even if I connected the radio ground to another seacock would they not be connected through the water... or am I overthinking it?
1) Do not connect a copper strap (or any other external ground connection) between the radio / transceiver, and anything else on-board!!!

It is "grounded" by the negative DC connection, and is grounded by the shield of the coax, and is grounded by the tuner control/power wiring....
All of these are protected and engineered ground connections, so they cause no issues....leave them alone...

{note, that using a "line isolator" on the coax (near the tuner end of the coax) does not remove the "ground" via the coax cable, but rather simply keeps RF from flowing on the outside of the coax shield....and installing a line isolator became de rigueur when Saillamil and other data comms started becoming popular, as this kept RF from the outside of the coax from causing computer and/or modem issues....}

Adding an additional "grounding" connection to the radio/transceiver on-board our boats, can unfortunately cause RFI problems!! And, as such, it is not recommended!
(take note that some have done it and not had issues, but most that have done so, have had multiple problems / issues, and have disconnected / removed it!)





Please let me repeat this, as it is important!

Do not connect a copper strap (or any other external ground connection) between the radio / transceiver, and anything else on-board!!!

That means, do not connect the radio to any other ground....

That means, do not connect the radio and tuner together by anything other than the coax and tuner control wires, and any ground wire provided with the tuner control wires....



I hope that is all clear now.....leave the radio alone!!!





2) Now to be clear, the "radio" and "tuner" are actually at the same ground potential....they are both grounded, together, to each other....
But, adding an additional / external grounding connection is what can cause problems / issues...



3) Please remember our small boats are more specialized / unique than any land installation, and even more than large ship installs....
We have our antennas radiating our transmit energy right next to the radio! Right next to other connected equipment!! With fiberglass / GRP being fairly invisible to RF, there is little to no isolation (as there is on large ships, and/or on land installations)...

So, what works for 99% of land installs just doesn't work well, nor work well reliably, on-board our boats....
Hence the reason the Sailmail Primer, etc. was written!!



4) Finally, except in the minds of the lawyers working for radio manufacturers, etc....nobody would recommend adding an additional grounding connection for the radio...


I hope this clears things up?

John
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