Willpatten
Member II
I want to install a SSB radio on my 1990 E38. I don't believe there is a grounding mat built into the hull since I haven't come across it. Any creative ideas for grounding a SSB on an E38 or any other Ericson for that matter?
Grounding a SSB
- Thread starter Willpatten
- Start date
Lew Decker
Member III
No one replied? There is a lot of info online and in print that addresses this issue but I can toss $.02 in the pot. In my experience, the single biggest factor in poor SSB performance is the ground system. RF can do some strange things, unlike AC or DC current. A ground system, if not properly done, can appear to the SSB as part of the antenna, and then it will detune itself trying to overcome what is a huge mismatch. This can lead to lower transmit output and will destroy the final power circuits over time.
So what is a good ground??? Get the widest and thickest copper strap you can manage and run the shortest route from the SSB to the engine block - which should already be grounded to the keel and the bonding system. This will give the appearance of a good ground right at the SSB itself, and the antenna tuner will love you forever. Just run a BIG strap (4" wide by 1/16" thick or better), not a thin 1/2" strip from your local plumbing supply house.
Good luck.
So what is a good ground??? Get the widest and thickest copper strap you can manage and run the shortest route from the SSB to the engine block - which should already be grounded to the keel and the bonding system. This will give the appearance of a good ground right at the SSB itself, and the antenna tuner will love you forever. Just run a BIG strap (4" wide by 1/16" thick or better), not a thin 1/2" strip from your local plumbing supply house.
Good luck.
windjunkee
Member III
We ran 4 inch wide copper from the radio back to the antenna tuner, shielding the cable that runs between the two. Then we bridges another strip of 4 inch copper down the side of the hull into the engine bilge where we bonded it to the forward cockpit drain thru-hull. It works great! We were in contact with the yacht club from Mexico (1200 miles) and they commented that it sounded like we were on a local telephone connection.
Jim McCone
Voice of Reason E-32-2 Hull #134
Redondo Beach, CA
Jim McCone
Voice of Reason E-32-2 Hull #134
Redondo Beach, CA
erobitaille
Member II
SSB Ground
Hello Guys,
I have a question. I must have hundreds of feet of 4" copper running all over my boat grounding every thing ( fuel tank, keel, engine block etc.). a lot of it is corroded and I wondering if a heavy gauge wire 6 or 0 could replace the SSB ground strap?
A ground is a ground is it not?
Hello Guys,
I have a question. I must have hundreds of feet of 4" copper running all over my boat grounding every thing ( fuel tank, keel, engine block etc.). a lot of it is corroded and I wondering if a heavy gauge wire 6 or 0 could replace the SSB ground strap?
A ground is a ground is it not?
Skin Effect, amounts etc
Ok so here I go with the professional secrets again.
1> It has to be foil. RF (Radio Frequency) energy travels along the skin atoms in the copper. On some frequencies it only travels in the electrons of the outer two atoms of the skin. Pretty thin. Wire especially marine grade wire has very small conductors bundled together. This is the least amount of skin that you can have in a conductor. So it has to be copper foil.
2> Grounding to the engine block is BAD. The engine block is not going to provide a good capacitance coupling device to the sea water around it. You will on most boats end up with very poor direct bond to the prop, which since RF is AC at big frequencies you don't want. Lets run though that: Bronze prop + stainless steel shaft= 2 dissimilar metals, RF= AC running through it == Potentials for electrolysis corrosion issues. Also having the ground from your alternator which is also a radio due to the way it works, feeding it's signal directly into the ground of your ssb should your engine be running while you are trying to listen to the weather, is not a great idea for noise.
3> Going over tanks is good but only if they are metal. A metal tank with the copper strap attached to it is a good thing. (NOTE NOT IF THE TANK IS ALUMINUM, the COPPER STRAP WILL EAT THROUGH THE TANK!). This gives the ground plane a larger area of ground plane which is what we are trying to do. It also in most cases gives us a cool effect called capacitance coupling to the water. (This is sometimes disputed by different people, I am on the side of capacitance coupling. The makers of sintered bronze blocks are not, cause well they make money if they can talk you into a sintered bronze block). ((RARE exception the sintered bronze block is some boats, maybe 1 in 300 or so just can't seem to get a descent ground no matter what you do. In those cases occasionally a sintered block will help with the little tiny extra metal that it provides in contact with the water.) In most boats they are just two more holes below the waterline that don't do anything except tempt fate.
3a> By all means grab 1 thru hull. 1, not all of them. You are making an RF ground not bonding the boat. The thru hull does not suffer the same fate as the prop, cause it is only one metal. Oh yeah it goes without saying, but lets say it anyway, plastic thru hulls, or thru hulls above the water do nothing for you. Don't bother connecting to them
4> How much copper you need. Most boats need about 25-50 feet of 2.5 to 3" copper strap. Toward the low end if you can go over the top of a tank, toward the high end if you can't. More than that and all you are doing is cutting your hands up every time that you go to get something out of a locker.
5> All this is for a modern automatic antenna tuners which should be installed as close the antenna feed point as possible. The cable from the radio to the tuner is COAX, and is therefore shielded already. Once the wire leaves the tuner, it is simply #10 wire with an extra heavy insulation coating on it. (NEVER USE COAX AFTER THE ANTENNA TUNER!) You can even get away with #10 wire in a pinch, although GTO wire is nicer as it has slightly more ability to reduce the chances of RF burns if someone grabs the GTO wire while someone is transmitting.
#6> If you have stainless steel lifelines, coated or not, it is a good idea to grab the bottom of one of the stantions in your grounding foil run. Generally I do this at the back of the boat in the cockpit lockers as far aft as possible, and actually connect to the pushpit. This takes a lot of the RF off of the lifelines which can help prevent RF burns should the crew grab the lifelines or pushpit while the radio operator is transmitting.
All this assumes that you have MODERN ELECTRONIC antenna tuner. If you have an old fiddle the capacitor nob, and a rolling inductor, or taped inductor, then you are more than likely going to have to spend a few hundred dollars lining the inside of the hull of your boat with copper foil. Since this is more money that the new tuner will cost you, I would recommend getting a new tuner.
#7> I am open for questions on installs if you want to ask them here.
Guy
Ok so here I go with the professional secrets again.
1> It has to be foil. RF (Radio Frequency) energy travels along the skin atoms in the copper. On some frequencies it only travels in the electrons of the outer two atoms of the skin. Pretty thin. Wire especially marine grade wire has very small conductors bundled together. This is the least amount of skin that you can have in a conductor. So it has to be copper foil.
2> Grounding to the engine block is BAD. The engine block is not going to provide a good capacitance coupling device to the sea water around it. You will on most boats end up with very poor direct bond to the prop, which since RF is AC at big frequencies you don't want. Lets run though that: Bronze prop + stainless steel shaft= 2 dissimilar metals, RF= AC running through it == Potentials for electrolysis corrosion issues. Also having the ground from your alternator which is also a radio due to the way it works, feeding it's signal directly into the ground of your ssb should your engine be running while you are trying to listen to the weather, is not a great idea for noise.
3> Going over tanks is good but only if they are metal. A metal tank with the copper strap attached to it is a good thing. (NOTE NOT IF THE TANK IS ALUMINUM, the COPPER STRAP WILL EAT THROUGH THE TANK!). This gives the ground plane a larger area of ground plane which is what we are trying to do. It also in most cases gives us a cool effect called capacitance coupling to the water. (This is sometimes disputed by different people, I am on the side of capacitance coupling. The makers of sintered bronze blocks are not, cause well they make money if they can talk you into a sintered bronze block). ((RARE exception the sintered bronze block is some boats, maybe 1 in 300 or so just can't seem to get a descent ground no matter what you do. In those cases occasionally a sintered block will help with the little tiny extra metal that it provides in contact with the water.) In most boats they are just two more holes below the waterline that don't do anything except tempt fate.
3a> By all means grab 1 thru hull. 1, not all of them. You are making an RF ground not bonding the boat. The thru hull does not suffer the same fate as the prop, cause it is only one metal. Oh yeah it goes without saying, but lets say it anyway, plastic thru hulls, or thru hulls above the water do nothing for you. Don't bother connecting to them
4> How much copper you need. Most boats need about 25-50 feet of 2.5 to 3" copper strap. Toward the low end if you can go over the top of a tank, toward the high end if you can't. More than that and all you are doing is cutting your hands up every time that you go to get something out of a locker.
5> All this is for a modern automatic antenna tuners which should be installed as close the antenna feed point as possible. The cable from the radio to the tuner is COAX, and is therefore shielded already. Once the wire leaves the tuner, it is simply #10 wire with an extra heavy insulation coating on it. (NEVER USE COAX AFTER THE ANTENNA TUNER!) You can even get away with #10 wire in a pinch, although GTO wire is nicer as it has slightly more ability to reduce the chances of RF burns if someone grabs the GTO wire while someone is transmitting.
#6> If you have stainless steel lifelines, coated or not, it is a good idea to grab the bottom of one of the stantions in your grounding foil run. Generally I do this at the back of the boat in the cockpit lockers as far aft as possible, and actually connect to the pushpit. This takes a lot of the RF off of the lifelines which can help prevent RF burns should the crew grab the lifelines or pushpit while the radio operator is transmitting.
All this assumes that you have MODERN ELECTRONIC antenna tuner. If you have an old fiddle the capacitor nob, and a rolling inductor, or taped inductor, then you are more than likely going to have to spend a few hundred dollars lining the inside of the hull of your boat with copper foil. Since this is more money that the new tuner will cost you, I would recommend getting a new tuner.
#7> I am open for questions on installs if you want to ask them here.
Guy
Last edited:
Howard Keiper
Moderator
I normally wouldn't argue with Guy,but much of his info is wrong. I accept some of it as gospel, however, as usual
Radio frequency energy especially aboard a boat is a different animal. For various reasons, a good RF ground need not be in contact with the sea at all, and for most practical purposes, shouldn't be. Thinking on the subject has changed a lot in recent decades. The general requirement for surface area exposed to the water (but not necessarily connected to it) hasn't changed too much at all.
A really good ground will come in two forms, ALWAYS copper foil, as Guy says, not the the thin, sissy stuff you get at WM, but substantial stuff fron a roofing supply house. Why? because thin copper foil will oxidize and crumble away like copper screen does. If you're going to create surface with copper, use substantial copper that you can screw or bolt to. If you have to connect strips or segments to achieve reasonable hull conformity. use capacitors, not wires.
A better way altogether is to haul the boat and Install cintered (sintered??) bronze "Dynaplates'. These things work really, really well even if they are an exception and are in direct contact with the sea. Every current authority now acknowledges their performance advantage.
You still end up dumping an enormous amount of RF current into the sea, but much more efficiently than with many of the older methods. When I do an installlation now I give the customer his choice: haul the boat and expect top performance, or pay me to crawl around in his bilge, and take you lumps.
Howard Keiper
Sea Quest
Berkeley
.
Radio frequency energy especially aboard a boat is a different animal. For various reasons, a good RF ground need not be in contact with the sea at all, and for most practical purposes, shouldn't be. Thinking on the subject has changed a lot in recent decades. The general requirement for surface area exposed to the water (but not necessarily connected to it) hasn't changed too much at all.
A really good ground will come in two forms, ALWAYS copper foil, as Guy says, not the the thin, sissy stuff you get at WM, but substantial stuff fron a roofing supply house. Why? because thin copper foil will oxidize and crumble away like copper screen does. If you're going to create surface with copper, use substantial copper that you can screw or bolt to. If you have to connect strips or segments to achieve reasonable hull conformity. use capacitors, not wires.
A better way altogether is to haul the boat and Install cintered (sintered??) bronze "Dynaplates'. These things work really, really well even if they are an exception and are in direct contact with the sea. Every current authority now acknowledges their performance advantage.
You still end up dumping an enormous amount of RF current into the sea, but much more efficiently than with many of the older methods. When I do an installlation now I give the customer his choice: haul the boat and expect top performance, or pay me to crawl around in his bilge, and take you lumps.
Howard Keiper
Sea Quest
Berkeley
.
25 years ago when I got my E27, I was an avid ham radio operator. I installed a mobile type "spider" antenna on the stern railing. From the base of the nearest stanchion I ran copper foil (about 4" wide") to my keel. I screwed the foil to the keel near the deep aft bilge "hole" where metal was obvious. I also ran foil from the back of my transceiver to the same keel point.
I had many contacts all over the U.S. and some foreign countries. A lot of people couldn't believe I was operating from a boat, because my signal was so loud.
25 years later the foil is still installed, but has corroded away in places. However, I don't use my radio anymore anyway.
I had many contacts all over the U.S. and some foreign countries. A lot of people couldn't believe I was operating from a boat, because my signal was so loud.
25 years later the foil is still installed, but has corroded away in places. However, I don't use my radio anymore anyway.
Dynaplate
This is a link to an old Sailnet thread where the Dynaplate gets mixed reviews. And there is collaboration of some points that Guy and Howard are making. I don't know, actually, so I am going to continue to investigate. Foil is definitely in. It sounds like my epoxy-encapsulated keel would work as a counterpoise.
http://www.sailnet.com/forums/gear-maintenance/906-ssb-ground-any-dynaplate-users.html
I have a ham friend who used to maintain everything electric powered on a fleet of work boats (power vessels). Maybe he has some relevant experience with HF onboard. I don't know if he has experience with sailboats in his past life, and even if he doesn't, he's good company. All he asks are a few navigation lessons. I think he is fascinated by the zig-zags and wants to figure out how we navigate. I hope he doesn't think we actually plot those zig-zags on charts and try to sail them.
Ellen and I just passed our General license exams this evening, so figuring this out has become a prize as shiny as new copper foil.
Cheers,
This is a link to an old Sailnet thread where the Dynaplate gets mixed reviews. And there is collaboration of some points that Guy and Howard are making. I don't know, actually, so I am going to continue to investigate. Foil is definitely in. It sounds like my epoxy-encapsulated keel would work as a counterpoise.
http://www.sailnet.com/forums/gear-maintenance/906-ssb-ground-any-dynaplate-users.html
I have a ham friend who used to maintain everything electric powered on a fleet of work boats (power vessels). Maybe he has some relevant experience with HF onboard. I don't know if he has experience with sailboats in his past life, and even if he doesn't, he's good company. All he asks are a few navigation lessons. I think he is fascinated by the zig-zags and wants to figure out how we navigate. I hope he doesn't think we actually plot those zig-zags on charts and try to sail them.
Ellen and I just passed our General license exams this evening, so figuring this out has become a prize as shiny as new copper foil.
Cheers,
Howard Keiper
Moderator
I admit that if I had a reasonably clean boat...doesn't even have to be new, that I could still be talked into installing copper inside the boat...maybe.
The thing is,copper doesn't stick to epoxy, most adhesives don't stick to oily surfaces, and it's a real pain in the ass to get a nice workable copper surface up close and comfortable to the inside of the hull where it does what it's supposed to...even small areas It's been my experience that eventually, the foil and or adhesive simply degrades to a point where it's worthless. I get paid by the hour to do this sort of thing and I at least like to think that when I'm finished, the job was done right and might last a couple of years.
Maybe I'm sniffing too much acetone or hot glue down in somebody's lazarette, but if a system (Dynaplate...two Dynaplates, actually), can be shown to produce the same results (and it can be, from all available evidence) as a well coppered install, then I'm all for it...oh yeah. And, the owner will be much more comfortable five years from now when he/she needs call home from Bora-Bora...and can.
Howard Keiper
Sea Quest
Berkeley
The thing is,copper doesn't stick to epoxy, most adhesives don't stick to oily surfaces, and it's a real pain in the ass to get a nice workable copper surface up close and comfortable to the inside of the hull where it does what it's supposed to...even small areas It's been my experience that eventually, the foil and or adhesive simply degrades to a point where it's worthless. I get paid by the hour to do this sort of thing and I at least like to think that when I'm finished, the job was done right and might last a couple of years.
Maybe I'm sniffing too much acetone or hot glue down in somebody's lazarette, but if a system (Dynaplate...two Dynaplates, actually), can be shown to produce the same results (and it can be, from all available evidence) as a well coppered install, then I'm all for it...oh yeah. And, the owner will be much more comfortable five years from now when he/she needs call home from Bora-Bora...and can.
Howard Keiper
Sea Quest
Berkeley
Dave Hussey
Member III
HAM radio swap meet
There is a BIG ham swap meet tomorrow (March 8, 2008) at the Puyallup fairground pavillion (Washington)... where you may find the answers to these questions, and perhaps come home with some new toys to boot
RF is as much sorcery as it is science, and the Wizzards I've worked with in the field as an electronics tech, (on aircraft)...all held the opinion that is: " if it worked, you got it right". (just make sure your transmitter always "sees" a load (impedence) within it's designed output (typically 50 to 300 ohms) which the antenna coupler is supposed to create between the output of the radio and the input to the transmission line.
73
N7BQV
There is a BIG ham swap meet tomorrow (March 8, 2008) at the Puyallup fairground pavillion (Washington)... where you may find the answers to these questions, and perhaps come home with some new toys to boot
RF is as much sorcery as it is science, and the Wizzards I've worked with in the field as an electronics tech, (on aircraft)...all held the opinion that is: " if it worked, you got it right". (just make sure your transmitter always "sees" a load (impedence) within it's designed output (typically 50 to 300 ohms) which the antenna coupler is supposed to create between the output of the radio and the input to the transmission line.
73
N7BQV