SSB :Larry Demers, et al

[Will Parker]

Larry Demers et al:
I installed a icom700 SSB on my CD30 shortly before I took my BERMUDA cruise. The prior owner of this boat had himself installed a ham setup which utilized about 15' of copper tubing instead of the copper foil which apparently is the preferred ground. It was connected between the dynaplate on the keel and the tuner which is located in the aft section of the port cockpit locker. I did not mess with his installation which he left intact in the boat. I found that while I could receive transmissions from great distances, I did not transmit very far and my signal was weak when it was heard. (I could hear "Southbound II" with great clarity but he could never read me). Also, bad weather just about put me off the air. I believe I could improve my system with the proper installation of the copper foil, and if I understand you guys correctly, this should be connected to its own dynaplate (I understand it should not be connected to same place as the lightning ground system), wound through the boat until it reaches the tuner, but avoiding the engine compartment. There doesn't seem to be any way to avoid the engine compartment if you are running something from the bilge to a cockpit locker? And is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel? Is there any useful way to add copper foil to the copper tubing already installed and improve transmission?
Help!
Will
"Jamabalaya"



whildenp@earthlink.net

[Ken Coit]

Will,

What a wonderful opportunity! Let's experiment with your boat.

The copper tubing is probably next to useless. Surface area is what RF grounds are all about and a copper tube doesn't have much. It may be a bit better than the same amount of copper in a solid wire, but even stranded wire would be an improvement. I suggest adding wide copper foil either in place of or in parallel with the tubing to see what difference it makes. It should be significant. Then I would start tieing in the other ground points that have been mentioned: fuel tank, bronze through hulls, lead keel, etc. If that isn't enough, then lining the easily accessible areas of the hull below the waterline with foil would be my next step. If you can set the 700 to a low power and gain access to a field strength meter which you can set some distance away, you ought to be able to detect when the point of diminishing returns is close at hand. As Larry has stated, once you have established the electrical equivalent of the other half of the antenna, no improvement will be had by adding more foil.

I don't claim to know much about keeping RF grounds and lightning grounds separate. Two dynaplates seems excessive to me, but again, RF energy likes a path with much surface area, so more is better to some extent.

We look forward to your report.

Keep on sailing,

Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC

Larry Demers et al:
I installed a icom700 SSB on my CD30 shortly before I took my BERMUDA cruise. The prior owner of this boat had himself installed a ham setup which utilized about 15' of copper tubing instead of the copper foil which apparently is the preferred ground. It was connected between the dynaplate on the keel and the tuner which is located in the aft section of the port cockpit locker. I did not mess with his installation which he left intact in the boat. I found that while I could receive transmissions from great distances, I did not transmit very far and my signal was weak when it was heard. (I could hear "Southbound II" with great clarity but he could never read me). Also, bad weather just about put me off the air. I believe I could improve my system with the proper installation of the copper foil, and if I understand you guys correctly, this should be connected to its own dynaplate (I understand it should not be connected to same place as the lightning ground system), wound through the boat until it reaches the tuner, but avoiding the engine compartment. There doesn't seem to be any way to avoid the engine compartment if you are running something from the bilge to a cockpit locker? And is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel? Is there any useful way to add copper foil to the copper tubing already installed and improve transmission?
Help!
Will
"Jamabalaya"

parfaitNOSPAM@nc.rr.com

[len]

ken

i don't understand radio but nevertheless successfully installed an icom SSB in my CD 31 several years ago and have had no difficultes whatsoever with it during solo cruises from boston to bermuda and boston to halifax

i followed gordon west's suggestions: antenna tuner is in the aft cockpit locker under the backstay - the whole system is linked via copper foil that is attached to two dynaplates, the base of the mast, at least 3 thru hulls and the engine -

the only problems i have had are corrosion where the foil was attached to the fuel tank (so i disconnected it from there) and corrosion of the foil under the engine (so i've now run it on the side of the engine compartment) -

i have no doubt this is not an ideal system BUT it was fairly easy to set-up and it works

len
CD31
hingham, ma



md.frel@nwh.org

[Ken Coit]

RF energy is funny stuff, it is not like running water or 12 VDC hookups. Overkill is usually the engineer's way of being certain that some combination will do the trick. Sounds like you have found one way that deals with the problem. Others can add your experience to their bag of tricks and probably save some time.

Keep on sailing,

Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC

ken

i don't understand radio but nevertheless successfully installed an icom SSB in my CD 31 several years ago and have had no difficultes whatsoever with it during solo cruises from boston to bermuda and boston to halifax

i followed gordon west's suggestions: antenna tuner is in the aft cockpit locker under the backstay - the whole system is linked via copper foil that is attached to two dynaplates, the base of the mast, at least 3 thru hulls and the engine -

the only problems i have had are corrosion where the foil was attached to the fuel tank (so i disconnected it from there) and corrosion of the foil under the engine (so i've now run it on the side of the engine compartment) -

i have no doubt this is not an ideal system BUT it was fairly easy to set-up and it works

len
CD31
hingham, ma

parfaitNOSPAM@nc.rr.com

[Larry DeMers]

Hi Will,

As Ken says, the pipe is not an RF ground..just a lossy ground wire for DC and perhaps some incidental frequencies along the way. This means that the transceiver has RF on the metal case and all over the front panel etc. It also means that some of your RF is not getting out of the boat, but is being turned into heat and is causing high VSWR ratios in the transmission line.

As others have said..replace that ground with a braided copper cable or copper foil sheet. The surface area of this sheet is needed to create a *low inductance* pathway for the ground. (High inductance paths, which you may have, tend to reject higher frequencies, allowing lower frequencies thru them, so the ground is choking off the HF frequencies to some extent, not allowing the full antenna "image" to be replicated in the ground path. This means then that you have a partial antenna (effectively). That is also why your transmitted signal was of low power or quality such that Herb could not hear you (hey, talked with Herb via e-mail..nice guy! Very dedicated. A group of us on Rec.boats.cruising tried to get the Queen of England to knight him for his work..no results so far, heh. Welll, they Knighted McCartney, didn't they?). Anyway, reception is not as strongly effected by this ground mismatch practicly, although your reception will improve also when the ground is working better.

Personally, I would recommend against bonding in anything other than the Dynaplates, and the seacocks. All the rest is already grounded thru another path, so you are creating a thing called a "Ground Loop".

This causes current to flow unevenly in the grounds. Since all conductors have some resistance and current pushed thru a resistive conductor drops some voltage, you end up with a potential difference in the ground circuit,between the two ends of the circuit. This will cause noise, rf reflections and create a poor ground.

It can also cause electrolysis on some of the connected objects, in the right configuration. I suspect that this is what Len found when he had the fuel tank tied in to the circuit.

Grounding for Ham/SSB is the toughest aspect to nail down perfectly, and usually is a step-by-step process. Starting with the simplest ground and working towards the most complex solution.

To your specific questions:

1. ...is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel?
Gordon West has shown at least some proof that yes it is. If you have a dynaplate for the rf ground, then I would use that in parallel with the closest thruhulls to the tuner, but would not extend this to the whole boats compliment of thru hulls. Try just the Dynaplate first and work up to the rest maybe.
JohnR and others have given some good advice about attaching the foil to a seacock securely and with anti-corrosion in mind. A gas tight connection is the best of course, so shoot for that..and use a dielectric grease over the mating surfaces to prevent oxidation.

2. ...is there any useful way to add copper foil to the copper tubing already installed and improve transmission?

None at all. Replace that with the foil or braided cable, and you will have a better ground.

I am curious to hear about how your SSB sigs improve and what you finally do to get them up to best performance. Each boat is so different from another, so the gnd. scheme always differs somewhat.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior

Larry Demers et al:
I installed a icom700 SSB on my CD30 shortly before I took my BERMUDA cruise. The prior owner of this boat had himself installed a ham setup which utilized about 15' of copper tubing instead of the copper foil which apparently is the preferred ground. It was connected between the dynaplate on the keel and the tuner which is located in the aft section of the port cockpit locker. I did not mess with his installation which he left intact in the boat. I found that while I could receive transmissions from great distances, I did not transmit very far and my signal was weak when it was heard. (I could hear "Southbound II" with great clarity but he could never read me). Also, bad weather just about put me off the air. I believe I could improve my system with the proper installation of the copper foil, and if I understand you guys correctly, this should be connected to its own dynaplate (I understand it should not be connected to same place as the lightning ground system), wound through the boat until it reaches the tuner, but avoiding the engine compartment. There doesn't seem to be any way to avoid the engine compartment if you are running something from the bilge to a cockpit locker? And is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel? Is there any useful way to add copper foil to the copper tubing already installed and improve transmission?
Help!
Will
"Jamabalaya"

demers@sgi.com

[will parker]

Thanks Larry, et al:
I appreciate the replies and I think you all have given me very useful information which will solve my problem.
will
"Jambalaya"

As Ken says, the pipe is not an RF ground..just a lossy ground wire for DC and perhaps some incidental frequencies along the way. This means that the transceiver has RF on the metal case and all over the front panel etc. It also means that some of your RF is not getting out of the boat, but is being turned into heat and is causing high VSWR ratios in the transmission line.

As others have said..replace that ground with a braided copper cable or copper foil sheet. The surface area of this sheet is needed to create a *low inductance* pathway for the ground. (High inductance paths, which you may have, tend to reject higher frequencies, allowing lower frequencies thru them, so the ground is choking off the HF frequencies to some extent, not allowing the full antenna "image" to be replicated in the ground path. This means then that you have a partial antenna (effectively). That is also why your transmitted signal was of low power or quality such that Herb could not hear you (hey, talked with Herb via e-mail..nice guy! Very dedicated. A group of us on Rec.boats.cruising tried to get the Queen of England to knight him for his work..no results so far, heh. Welll, they Knighted McCartney, didn't they?). Anyway, reception is not as strongly effected by this ground mismatch practicly, although your reception will improve also when the ground is working better.

Personally, I would recommend against bonding in anything other than the Dynaplates, and the seacocks. All the rest is already grounded thru another path, so you are creating a thing called a "Ground Loop".

This causes current to flow unevenly in the grounds. Since all conductors have some resistance and current pushed thru a resistive conductor drops some voltage, you end up with a potential difference in the ground circuit,between the two ends of the circuit. This will cause noise, rf reflections and create a poor ground.

It can also cause electrolysis on some of the connected objects, in the right configuration. I suspect that this is what Len found when he had the fuel tank tied in to the circuit.

Grounding for Ham/SSB is the toughest aspect to nail down perfectly, and usually is a step-by-step process. Starting with the simplest ground and working towards the most complex solution.

To your specific questions:

1. ...is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel?
Gordon West has shown at least some proof that yes it is. If you have a dynaplate for the rf ground, then I would use that in parallel with the closest thruhulls to the tuner, but would not extend this to the whole boats compliment of thru hulls. Try just the Dynaplate first and work up to the rest maybe.
JohnR and others have given some good advice about attaching the foil to a seacock securely and with anti-corrosion in mind. A gas tight connection is the best of course, so shoot for that..and use a dielectric grease over the mating surfaces to prevent oxidation.

2. ...is there any useful way to add copper foil to the copper tubing already installed and improve transmission?

None at all. Replace that with the foil or braided cable, and you will have a better ground.

I am curious to hear about how your SSB sigs improve and what you finally do to get them up to best performance. Each boat is so different from another, so the gnd. scheme always differs somewhat.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior

Larry Demers et al:
I installed a icom700 SSB on my CD30 shortly before I took my BERMUDA cruise. The prior owner of this boat had himself installed a ham setup which utilized about 15' of copper tubing instead of the copper foil which apparently is the preferred ground. It was connected between the dynaplate on the keel and the tuner which is located in the aft section of the port cockpit locker. I did not mess with his installation which he left intact in the boat. I found that while I could receive transmissions from great distances, I did not transmit very far and my signal was weak when it was heard. (I could hear "Southbound II" with great clarity but he could never read me). Also, bad weather just about put me off the air. I believe I could improve my system with the proper installation of the copper foil, and if I understand you guys correctly, this should be connected to its own dynaplate (I understand it should not be connected to same place as the lightning ground system), wound through the boat until it reaches the tuner, but avoiding the engine compartment. There doesn't seem to be any way to avoid the engine compartment if you are running something from the bilge to a cockpit locker? And is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel? Is there any useful way to add copper foil to the copper tubing already installed and improve transmission?
Help!
Will
"Jamabalaya"

whildenp@earthlink.net

[will parker]

Thanks Larry, et al:
I appreciate the replies and I think you all have given me very useful information which will solve my problem.
will
"Jambalaya"

As Ken says, the pipe is not an RF ground..just a lossy ground wire for DC and perhaps some incidental frequencies along the way. This means that the transceiver has RF on the metal case and all over the front panel etc. It also means that some of your RF is not getting out of the boat, but is being turned into heat and is causing high VSWR ratios in the transmission line.

As others have said..replace that ground with a braided copper cable or copper foil sheet. The surface area of this sheet is needed to create a *low inductance* pathway for the ground. (High inductance paths, which you may have, tend to reject higher frequencies, allowing lower frequencies thru them, so the ground is choking off the HF frequencies to some extent, not allowing the full antenna "image" to be replicated in the ground path. This means then that you have a partial antenna (effectively). That is also why your transmitted signal was of low power or quality such that Herb could not hear you (hey, talked with Herb via e-mail..nice guy! Very dedicated. A group of us on Rec.boats.cruising tried to get the Queen of England to knight him for his work..no results so far, heh. Welll, they Knighted McCartney, didn't they?). Anyway, reception is not as strongly effected by this ground mismatch practicly, although your reception will improve also when the ground is working better.

Personally, I would recommend against bonding in anything other than the Dynaplates, and the seacocks. All the rest is already grounded thru another path, so you are creating a thing called a "Ground Loop".

This causes current to flow unevenly in the grounds. Since all conductors have some resistance and current pushed thru a resistive conductor drops some voltage, you end up with a potential difference in the ground circuit,between the two ends of the circuit. This will cause noise, rf reflections and create a poor ground.

It can also cause electrolysis on some of the connected objects, in the right configuration. I suspect that this is what Len found when he had the fuel tank tied in to the circuit.

Grounding for Ham/SSB is the toughest aspect to nail down perfectly, and usually is a step-by-step process. Starting with the simplest ground and working towards the most complex solution.

To your specific questions:

1. ...is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel?
Gordon West has shown at least some proof that yes it is. If you have a dynaplate for the rf ground, then I would use that in parallel with the closest thruhulls to the tuner, but would not extend this to the whole boats compliment of thru hulls. Try just the Dynaplate first and work up to the rest maybe.
JohnR and others have given some good advice about attaching the foil to a seacock securely and with anti-corrosion in mind. A gas tight connection is the best of course, so shoot for that..and use a dielectric grease over the mating surfaces to prevent oxidation.

2. ...is there any useful way to add copper foil to the copper tubing already installed and improve transmission?

None at all. Replace that with the foil or braided cable, and you will have a better ground.

I am curious to hear about how your SSB sigs improve and what you finally do to get them up to best performance. Each boat is so different from another, so the gnd. scheme always differs somewhat.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior

Larry Demers et al:
I installed a icom700 SSB on my CD30 shortly before I took my BERMUDA cruise. The prior owner of this boat had himself installed a ham setup which utilized about 15' of copper tubing instead of the copper foil which apparently is the preferred ground. It was connected between the dynaplate on the keel and the tuner which is located in the aft section of the port cockpit locker. I did not mess with his installation which he left intact in the boat. I found that while I could receive transmissions from great distances, I did not transmit very far and my signal was weak when it was heard. (I could hear "Southbound II" with great clarity but he could never read me). Also, bad weather just about put me off the air. I believe I could improve my system with the proper installation of the copper foil, and if I understand you guys correctly, this should be connected to its own dynaplate (I understand it should not be connected to same place as the lightning ground system), wound through the boat until it reaches the tuner, but avoiding the engine compartment. There doesn't seem to be any way to avoid the engine compartment if you are running something from the bilge to a cockpit locker? And is attaching the foil to a seacock an acceptable alternative to attachment to a dynaplate on the keel? Is there any useful way to add copper foil to the copper tubing already installed and improve transmission?
Help!
Will
"Jamabalaya"

whildenp@earthlink.net