Ground for SSB or Ham Radio

[Jim Stull]

I would appreciate info on what has been found to be effective grounding for an SSB or ham radio installation. Any other related suggestions would also be most welcome.
Thanks
Jim



jtstull@earthlink.net

[Larry DeMers]

For ham use, I installed a capacative grounding system made of expanded copper foil. This foil was cut and placed in the bilge, up the sides of the bilge, and all the way forward to the head area, as well as some under the cockpit originally (gone now). All pieces were joined and soldered together to form one piece electrically. Next, the screening was grounded to the ships bonding system **in one place only**(in order to bring this ground in to play also..you may not need to do this as it's effectiveness is not proven on my boat).
I use a small antenna tuner when hamming, and regularly can get a 1:1.2 VSWR on my rig. My trouble is finding a spot to permanently install the gear. So far, I end up using the cockpit as my station as much as the cabin. Kinda cool tuning a dx station and swinging at anchor too! But it all has to be put away when done.So I do my ahmming mostly at home now..and then.

There are some really good books out about ham radio on boats..antennas too..another favorite topic of mine. Do a net search on "ham radio boats".

Cheers!

Larry DeMers
s/v DeLaMer
Cape Dory 30

I would appreciate info on what has been found to be effective grounding for an SSB or ham radio installation. Any other related suggestions would also be most welcome.
Thanks
Jim

demers@sgi.com

[len]

jim

i have an icom SSB (on the starboard side just forward of the galley) and an icom antenna tuner - i have a backstay antenna - i installed a second grounding plate and used copper foil (available from west marine or any marine electronic store) to ground it - gordon west (i'm sure he has a web site) has written instructions that come with the foil, basically he advises connecting everything metal on the boat and at least 3 of the through-hulls - after 5 years the foil i had (in retrospect a mistake) run under the engine was deteriorating so i have run some new foil in other ways - by the way the antenna tuner has to be close to the antenna, mine is under the deck at the stern, a pain to install but once it's there you don't have to touch it - my reception has been excellent - however, a major problem with SSB now is that AT and T which once had 3 powerful shore stations gave up a couple of years ago and the only commercial station still operating only has one station - in a pinch i have used the coast guard channels and they have been kind enough to call home for me - i think ham is an excellent alternative or addition but haven't gotten into that, i can only get offshore once yearly and consider the radio fundamentally a piece of emergency equipment - hope this lengthy reply of some use and am interested in others' experiences

len



md.frel@nwh.org

[Jim Stull]

Thanks to both Len and Larry for the most helpful replys
Jim



jtstull@earthlink.net

[John R.]

I would appreciate info on what has been found to be effective grounding for an SSB or ham radio installation. Any other related suggestions would also be most welcome.
Thanks
Jim

I've used several different methods in the past for a counterpoise. I like roofing copper sheet. It is about 3/32" thick and very durable. You can cut srips and solder them together into a grid and glass that assembly to the inside of the hull or you can just use full sheets or cut from a roll. It comes in varying lengths and widths. Look in your yellow pages for roofing materials suppliers. Don't waste your money on the junk foils in marine stores, it's a total waste. The only exception is either Newmar or G. West because one of them makes a heavy thickness copper strapping, not a typical cheap foil. Remember the total surface area of the counterpoise is whats important. The thickness is only important for durability, it has absolutely nothing to do with radio performance.

You can use bronze screen as well. It can be had from Defender et al. Currently we have a Icom M700TY on board with the 120 auto tuner and an insulated backstay, the rig works just fine. Your SSB owners manual should give you complete suggestions for setting up the best counterpoise for your given situation. If you don't have the manual you would be wise to get one.

[Ken Coit]

How about some estimates of area? I understand more is better, but I also understand the law of diminishing returns. What do the experts recommend? If the counterpoise is tied into the bonding and grounding for lightning, is there anything to be gained by trying to locate it appropriately? Where is that?

Ken

I would appreciate info on what has been found to be effective grounding for an SSB or ham radio installation. Any other related suggestions would also be most welcome.
Thanks
Jim

I've used several different methods in the past for a counterpoise. I like roofing copper sheet. It is about 3/32" thick and very durable. You can cut srips and solder them together into a grid and glass that assembly to the inside of the hull or you can just use full sheets or cut from a roll. It comes in varying lengths and widths. Look in your yellow pages for roofing materials suppliers. Don't waste your money on the junk foils in marine stores, it's a total waste. The only exception is either Newmar or G. West because one of them makes a heavy thickness copper strapping, not a typical cheap foil. Remember the total surface area of the counterpoise is whats important. The thickness is only important for durability, it has absolutely nothing to do with radio performance.

You can use bronze screen as well. It can be had from Defender et al. Currently we have a Icom M700TY on board with the 120 auto tuner and an insulated backstay, the rig works just fine. Your SSB owners manual should give you complete suggestions for setting up the best counterpoise for your given situation. If you don't have the manual you would be wise to get one.

parfait@nc.rr.com

[Ken Coit]

Answering my own question - 100 sq. ft. or greater is what Farallon Electronics recommends. Since surface area is the issue, I wonder if a wide braid might work well; it could be buried in resin against the hull. There is lots of info on marine HF installations can be found at the link below.

Ken

How about some estimates of area? I understand more is better, but I also understand the law of diminishing returns. What do the experts recommend? If the counterpoise is tied into the bonding and grounding for lightning, is there anything to be gained by trying to locate it appropriately? Where is that?

Ken

I would appreciate info on what has been found to be effective grounding for an SSB or ham radio installation. Any other related suggestions would also be most welcome.
Thanks
Jim

I've used several different methods in the past for a counterpoise. I like roofing copper sheet. It is about 3/32" thick and very durable. You can cut srips and solder them together into a grid and glass that assembly to the inside of the hull or you can just use full sheets or cut from a roll. It comes in varying lengths and widths. Look in your yellow pages for roofing materials suppliers. Don't waste your money on the junk foils in marine stores, it's a total waste. The only exception is either Newmar or G. West because one of them makes a heavy thickness copper strapping, not a typical cheap foil. Remember the total surface area of the counterpoise is whats important. The thickness is only important for durability, it has absolutely nothing to do with radio performance.

You can use bronze screen as well. It can be had from Defender et al. Currently we have a Icom M700TY on board with the 120 auto tuner and an insulated backstay, the rig works just fine. Your SSB owners manual should give you complete suggestions for setting up the best counterpoise for your given situation. If you don't have the manual you would be wise to get one.

parfait@nc.rr.com

[Jim Stull]

Your reference site is great.
Thanks very much.
Jim



jtstull@earthlink.net

[Jim Stull]

Hi John
I not only don't have the manual, I don't even have the radio yet.
We are about to begin a 2 year hull-up total rebuild and have the option to do pretty much anything reasonable to end up with a good rig.
Thanks for the ideas.
Jim



jtstull@earthlink.net

[John R.]

Ken,

That is an excellent reference site for anyone contemplating a SSB install. It is very well presented. There are a couple points that were not mentioned (that I did not notice) that need to be pointed out. I have never seen more than two recreational boats with excellent SSB counterpoise systems which have incorporated their bow pulpits, stern rails and lifelines into the RF ground. I don't think it's usually necessary because I've experienced many other counterpoise systems that worked perfectly without those components being utilized.

A person could use a very large Dynaplate as the necessary RF ground surface area as long as it is tied properly to the vessel common ground point. In this case the surface area of the connecting strapping is critical and equally so is the durability.

The braid you mention is an interesting idea. I would venture to say that it may perform similar to screen. But I emphasize "may". I would assume that the surface area of all the individual strands which make up the braid would or could equal the surface area of a given amount of screen. It would be very difficult to determine what the area of the braid would need to be to afford the minimum surface needed for the RF. That is the problem with stranded copper wire, you would have to have a huge diameter wire to obtain enough surface area within the wire.

A 3 - 4" wide strip of copper sheet would require one hell of a lot of strands within any braid to match the surface area of the copper strip. Keep in mind we are talking about both sides of the strip. The more I think about braid the less excited I would tend to be about it. I would stick to copper strap or sheet, we know it works and works extremely well. I see no advantage to using braid over copper strap or screening even if it were proven to be a suitable material to build a counterpoise with. Screen and strip/strap have been around for a longtime and are still the standard materials used.

[Ken Coit]

I agree with your assessment of the braid question. Screening and straping make more sense. I guess the screen would be a bit easier to fit to the hull in large areas.

As for the lifelines, bow pulpit and pushpit, I wonder if it may be more a matter of making them part of the solution rather than a potential problem. It would not be good for them to be hot with RF.

Gordon West published something for the Marion Bermuda race a while back that indicates that having a solid connection to the salt water can be of large benefit. He recommends tieing into a least one through hull fitting. I wonder if they are all bonded, whether connecting to several could cause ground loops and electrolysis loops that might not be helpful. See the link for more from Gordon West.

Ken

Ken,

That is an excellent reference site for anyone contemplating a SSB install. It is very well presented. There are a couple points that were not mentioned (that I did not notice) that need to be pointed out. I have never seen more than two recreational boats with excellent SSB counterpoise systems which have incorporated their bow pulpits, stern rails and lifelines into the RF ground. I don't think it's usually necessary because I've experienced many other counterpoise systems that worked perfectly without those components being utilized.

A person could use a very large Dynaplate as the necessary RF ground surface area as long as it is tied properly to the vessel common ground point. In this case the surface area of the connecting strapping is critical and equally so is the durability.

The braid you mention is an interesting idea. I would venture to say that it may perform similar to screen. But I emphasize "may". I would assume that the surface area of all the individual strands which make up the braid would or could equal the surface area of a given amount of screen. It would be very difficult to determine what the area of the braid would need to be to afford the minimum surface needed for the RF. That is the problem with stranded copper wire, you would have to have a huge diameter wire to obtain enough surface area within the wire.

A 3 - 4" wide strip of copper sheet would require one hell of a lot of strands within any braid to match the surface area of the copper strip. Keep in mind we are talking about both sides of the strip. The more I think about braid the less excited I would tend to be about it. I would stick to copper strap or sheet, we know it works and works extremely well. I see no advantage to using braid over copper strap or screening even if it were proven to be a suitable material to build a counterpoise with. Screen and strip/strap have been around for a longtime and are still the standard materials used.

parfait@nc.rr.com

[Don Craig]

I've been fascinated with ham antennas since I got my first license as a teenage geek. About 15 years ago I put a ham rig aboard a Bristol Channel Cutter prior to a long cruise. I went through the whole agony of the counterpoise/bonding/Dynaplate debate. I wanted the least complicated system that would WORK. I decided to try a top-fed, inverted-V dipole "with a twist"--the twist was that the mast/ballast/rigging would be the counterpoise. With the mast off prior to launch, I installed an insulated backstay with the top insulator within a foot of the masthead, bottom insulator a little above the height where someone would be inclined to grab the energized portion while standing on deck. I installed an 12x3 Dynaplate on the hull. Aluminum mast on this boat was keel-stepped and the mast step fitting was already bolted into the internal lead keel--main point is to have the mast and metal ballast electrically bonded. I ran a low-loss 52-ohm coax (think it was RG-213U/MilSpec) from the output of the automatic antenna tuner (through an antenna switch at the nav station) up to the top of the mast--right alongside the VHF cable. At the truck, the core is separated from the braid where the cable emerges from the mast. Core is brought down and clamped to the insulated portion of the backstay right next to the insulator. Braid (already tinned) is covered with heat-shrink, crimp connector on end, and screwed into the mast in a new drilled & tapped hole. The ground system at the radio is connected to the Dynaplate. (I also set it up so that the backstay was switched to the Dynaplate ground when radio wasn't in use--extra lightning ground). The tuner was able to quickly tune all frequencies on this setup with negligible SWR's; full power was getting out. None of the rigging ever tested "hot." I realize this alternative would not be suitable for many boats here, but it seems to be a very clean, lower cost (and labor) alterntive to straps and screens. I was able to make phone and CW contacts in Europe, Asia and Australia from the Great Lakes and East Coast. Bottom line: A "counterpoise" of some kind is necessary, but you'd be surprised at what you can get away with an antenna tuner, auto or manual.

I would appreciate info on what has been found to be effective grounding for an SSB or ham radio installation. Any other related suggestions would also be most welcome.
Thanks
Jim

dlaurence@msn.com

[John MacArthur]

I would appreciate info on what has been found to be effective grounding for an SSB or ham radio installation. Any other related suggestions would also be most welcome.
Thanks
Jim

I just use a "Hamstick" whip antenna attached to the stern pulpit, and a 15' piece of soft rigging wire vise-gripped to the base and thrown in the water. I use this for ham communication from my winter cruising grounds in the Mexico. It has worked adequately for my needs for quite a few years. Someday I probably will install an insulated backstay and foil counterpoise, but I will have to have more "spare time"!

KJ5UR



jmac@laplaza.org

[John R.]

I agree with your assessment of the braid question. Screening and straping make more sense. I guess the screen would be a bit easier to fit to the hull in large areas.

As for the lifelines, bow pulpit and pushpit, I wonder if it may be more a matter of making them part of the solution rather than a potential problem. It would not be good for them to be hot with RF.

Gordon West published something for the Marion Bermuda race a while back that indicates that having a solid connection to the salt water can be of large benefit. He recommends tieing into a least one through hull fitting. I wonder if they are all bonded, whether connecting to several could cause ground loops and electrolysis loops that might not be helpful. See the link for more from Gordon West.

Ken

Ken,

That is an excellent reference site for anyone contemplating a SSB install. It is very well presented. There are a couple points that were not mentioned (that I did not notice) that need to be pointed out. I have never seen more than two recreational boats with excellent SSB counterpoise systems which have incorporated their bow pulpits, stern rails and lifelines into the RF ground. I don't think it's usually necessary because I've experienced many other counterpoise systems that worked perfectly without those components being utilized.

A person could use a very large Dynaplate as the necessary RF ground surface area as long as it is tied properly to the vessel common ground point. In this case the surface area of the connecting strapping is critical and equally so is the durability.

The braid you mention is an interesting idea. I would venture to say that it may perform similar to screen. But I emphasize "may". I would assume that the surface area of all the individual strands which make up the braid would or could equal the surface area of a given amount of screen. It would be very difficult to determine what the area of the braid would need to be to afford the minimum surface needed for the RF. That is the problem with stranded copper wire, you would have to have a huge diameter wire to obtain enough surface area within the wire.

A 3 - 4" wide strip of copper sheet would require one hell of a lot of strands within any braid to match the surface area of the copper strip. Keep in mind we are talking about both sides of the strip. The more I think about braid the less excited I would tend to be about it. I would stick to copper strap or sheet, we know it works and works extremely well. I see no advantage to using braid over copper strap or screening even if it were proven to be a suitable material to build a counterpoise with. Screen and strip/strap have been around for a longtime and are still the standard materials used.

Ken,
That is another excellent post regarding the SSB. Yes, in general screening is easier because it is more conformable to the hull shape with the exception of foil. But foil is more susceptible to damage, it just is. As Gordon states it can and should be painted over or coated with resin. Nonetheless it still is easily damaged if the overcoat is penetrated. Screen is stronger and you don't have to go through all the strip connections, it's all one sheet, like roofing copper. The later being heavier, less conformable and harder to work with but more durable than anything else.

The lifelines, pulpit, rail, etc would not be hot because they would be isolated from your GTO connection which would be limited to your isolated backstay.

Gordon's articles have always stated the recommendation to tie into several underwater thru hulls to make it easier to use salt water as the counterpoise. As he states it does minimize the need for extensive foiling or screening inside the hull but there is the risk of poor connections developing. I believe the recommendation is to utilize several thru hulls not just one. They must be bonded. The theory is as long as the foil or screen is kept out of the bilge water then stray current corossion is not an issue. Personally I'm not so sure that would always be the case. It is my opinion that dampness alone could set up the conditions to create with the foil the stray current scenario, which would probably be very minimal. However, using large metal objects to help make up the counterpoise also holds potential for stray current problems.

I found the point he made about utilizing the poured lead keel an interesting one. I have not done that but may do so. I've never drilled into the CD keel to any great degree but will be thinking about doing so. Perhaps run a length of copper strip to a bronze lag bolt screwed deep into the keel. It seems to me that the keel in combination with the stripping I have would create a huge counterpoise and give the signal an immense bounce and be very clear and strong.