Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
mthorpe@capecod.net
Testing SSB Ground????
Moderator: Jim Walsh
-
Larry DeMers
Re: Testing SSB Ground????
Your SSB ground is supposed to be a good RF ground, so the testing that would reveal it's quality would involve sendingRF of the frequencies you are interested in over your antenna/ground combination and observing the VSWR returned from the antenna. In short..using it and then measuring the performance while in operation.
One way to scope it out ahead of time is to describe the grounding system precisely to us, and lets see what it consists of. Another would be to use some equipment to measure the reactance of that ground circuit, and see if it is low enough at your operating frequencies, but this requires specialized equipment, like the MFJ antenna analyzer box that Ken talked about last week. This box would output an rf sig. in the freq. range of interest, and would then read the VSWR of that ground. It should be in resonance (SWR of less than 1:1.8) at the freq. you are using.
How about a description of the grounding path?
Cheers,
Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior
ex-K0INX for 30 years
demers@sgi.com
One way to scope it out ahead of time is to describe the grounding system precisely to us, and lets see what it consists of. Another would be to use some equipment to measure the reactance of that ground circuit, and see if it is low enough at your operating frequencies, but this requires specialized equipment, like the MFJ antenna analyzer box that Ken talked about last week. This box would output an rf sig. in the freq. range of interest, and would then read the VSWR of that ground. It should be in resonance (SWR of less than 1:1.8) at the freq. you are using.
How about a description of the grounding path?
Cheers,
Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior
ex-K0INX for 30 years
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
demers@sgi.com
-
Mike Thorpe
Re: Testing SSB Ground????
Larry,
Thanks for responding. The ground that I put in consists of 3" wide copper foil running from underneath the backstay chainplate forward under the engine where it is wrapped and fastened with hose clamps to (2) bronze seacocks. From there it continues forward into the bilge. In the bilge it is bolted to a lug on the existing dynaplate and then runs up and is bolted to the ground lug for the fuel tank which is located under the cabin sole. The fuel tank is approximately 3'wide x 6'long. It then runs under the starboard settee, through a bulkhead and into a small hanging locker under the Nav station. The entire run is one piece and is covered with epoxy and fiberglass tape to protect it. Also, there is several extra feet of foil coiled on each end for attaching the antenna tuner and radio.
What do you think?
Mike Thorpe
CD-36 Journey's End
Hyannis, MA
mthorpe@capecod.net
Thanks for responding. The ground that I put in consists of 3" wide copper foil running from underneath the backstay chainplate forward under the engine where it is wrapped and fastened with hose clamps to (2) bronze seacocks. From there it continues forward into the bilge. In the bilge it is bolted to a lug on the existing dynaplate and then runs up and is bolted to the ground lug for the fuel tank which is located under the cabin sole. The fuel tank is approximately 3'wide x 6'long. It then runs under the starboard settee, through a bulkhead and into a small hanging locker under the Nav station. The entire run is one piece and is covered with epoxy and fiberglass tape to protect it. Also, there is several extra feet of foil coiled on each end for attaching the antenna tuner and radio.
What do you think?
Mike Thorpe
CD-36 Journey's End
Hyannis, MA
Larry DeMers wrote: Your SSB ground is supposed to be a good RF ground, so the testing that would reveal it's quality would involve sendingRF of the frequencies you are interested in over your antenna/ground combination and observing the VSWR returned from the antenna. In short..using it and then measuring the performance while in operation.
One way to scope it out ahead of time is to describe the grounding system precisely to us, and lets see what it consists of. Another would be to use some equipment to measure the reactance of that ground circuit, and see if it is low enough at your operating frequencies, but this requires specialized equipment, like the MFJ antenna analyzer box that Ken talked about last week. This box would output an rf sig. in the freq. range of interest, and would then read the VSWR of that ground. It should be in resonance (SWR of less than 1:1.8) at the freq. you are using.
How about a description of the grounding path?
Cheers,
Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior
ex-K0INX for 30 years
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
mthorpe@capecod.net
-
Ken Coit
Re: Testing SSB Ground????
Mike,
Just connecting a SSB transmitter and seeing how it does, what the SWR is, etc., may not be enough. Certainly the antenna analyzer will help as Larry points out, but the real test is to add more ground plane temporarily to see what affect it has. Check out the link below for a methodology that might be adopted for marine SSB.
I think that Andy Denmark also posted some experimental results by the Seven Seas Assoc. on this board several months ago.
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
parfaitNOSPAM@nc.rr.com
Just connecting a SSB transmitter and seeing how it does, what the SWR is, etc., may not be enough. Certainly the antenna analyzer will help as Larry points out, but the real test is to add more ground plane temporarily to see what affect it has. Check out the link below for a methodology that might be adopted for marine SSB.
I think that Andy Denmark also posted some experimental results by the Seven Seas Assoc. on this board several months ago.
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
parfaitNOSPAM@nc.rr.com
-
len
Re: Testing SSB Ground????
mike
i connected my foil to my fuel tank and it led to corrosion of the fuel tank so watch out for that - i also connected the foil to several thru hulls (using hose clamps around the base of the thru hull after sanding it there to make a good electrical connection), to the base of the mast, to the engine block, and to the base of the steering pedestal -
len
md.frel@nwh.org
i connected my foil to my fuel tank and it led to corrosion of the fuel tank so watch out for that - i also connected the foil to several thru hulls (using hose clamps around the base of the thru hull after sanding it there to make a good electrical connection), to the base of the mast, to the engine block, and to the base of the steering pedestal -
len
md.frel@nwh.org
-
Larry DeMers
Re: Testing SSB Ground????
Mike,
You have a capacitively coupled ground system with some direct connections to ground. This should work quite well, but it all depends on the freq's that you use. There is no setup that works well for all boats. For instance, I can load up my standing rigging, even though it is grounded at many places. The results I get will be specific to my boat only..not even to the fleet of boats like it. This is because of the many factors that effect the resonance of an antenna and the ground.
Interestingly, Gordon West..a radio comms 'expert', did some half-baked tests a few years back, and found that merely connecting the thru hulls and prop shaft to the SSB ground was sufficient to get on the air well. I think he had another of those specific cases where you do something then make the fatal mistake of trying to invoke it universally. His experiment went fine for his boat..and in fact, I remember as a ham operator, loading up my bedrooms window screen as a transmitting antenna once. It worked ok, but I was in the rf field of course..bad idea.
What I would recommend is that you get the radio hooked up..connect up the antenna tuner (you did not mention this..you have one, no?), then grounds and try it out..use a VSWR meter to check on transmitted power vs. reflected, and adjust to minimize this. If you note RF on the grounds inside the boat, there is too much VSWR on the ground lead. You can approach this in several ways. One time,. I said the hell with it, and put a cheap manual antenna tuner into the ground lead from the rig to the ground rod. After tuning the antenna, I tuned the ground for resonance, and this helped take the rf away fromt he rig, and it upped my total power out. You may get to this point eventually, but try several ideas for grounding first.
I think that your ground is about as good as they get without having the copper foil buried in the hull itself. I am not sure about including the lightning bonding system in the network though (when you say the fuel tank and other metalic objects are tied into this ground net, that says that the lightning bonding system is included. I think that is a mistake, due to the meandering path that the rf ground takes. I have learned the hard way..rf grounds are a ground at a specific frequency only..otherwise they oscillate from a ground to a complete OPEN rf-wise as the freq's are varied. So a long involved ground line is really a nice DC ground..and a lightning flash-over protection possibly, but it is not a good rf ground. That path needs to be a direct line to the ground shoe and foil.
So try what is there now, see how it performs, then make incremental changes and retest over time.
Cheers,
Larry DeMers
demers@sgi.com
You have a capacitively coupled ground system with some direct connections to ground. This should work quite well, but it all depends on the freq's that you use. There is no setup that works well for all boats. For instance, I can load up my standing rigging, even though it is grounded at many places. The results I get will be specific to my boat only..not even to the fleet of boats like it. This is because of the many factors that effect the resonance of an antenna and the ground.
Interestingly, Gordon West..a radio comms 'expert', did some half-baked tests a few years back, and found that merely connecting the thru hulls and prop shaft to the SSB ground was sufficient to get on the air well. I think he had another of those specific cases where you do something then make the fatal mistake of trying to invoke it universally. His experiment went fine for his boat..and in fact, I remember as a ham operator, loading up my bedrooms window screen as a transmitting antenna once. It worked ok, but I was in the rf field of course..bad idea.
What I would recommend is that you get the radio hooked up..connect up the antenna tuner (you did not mention this..you have one, no?), then grounds and try it out..use a VSWR meter to check on transmitted power vs. reflected, and adjust to minimize this. If you note RF on the grounds inside the boat, there is too much VSWR on the ground lead. You can approach this in several ways. One time,. I said the hell with it, and put a cheap manual antenna tuner into the ground lead from the rig to the ground rod. After tuning the antenna, I tuned the ground for resonance, and this helped take the rf away fromt he rig, and it upped my total power out. You may get to this point eventually, but try several ideas for grounding first.
I think that your ground is about as good as they get without having the copper foil buried in the hull itself. I am not sure about including the lightning bonding system in the network though (when you say the fuel tank and other metalic objects are tied into this ground net, that says that the lightning bonding system is included. I think that is a mistake, due to the meandering path that the rf ground takes. I have learned the hard way..rf grounds are a ground at a specific frequency only..otherwise they oscillate from a ground to a complete OPEN rf-wise as the freq's are varied. So a long involved ground line is really a nice DC ground..and a lightning flash-over protection possibly, but it is not a good rf ground. That path needs to be a direct line to the ground shoe and foil.
So try what is there now, see how it performs, then make incremental changes and retest over time.
Cheers,
Larry DeMers
Mike Thorpe wrote: Larry,
Thanks for responding. The ground that I put in consists of 3" wide copper foil running from underneath the backstay chainplate forward under the engine where it is wrapped and fastened with hose clamps to (2) bronze seacocks. From there it continues forward into the bilge. In the bilge it is bolted to a lug on the existing dynaplate and then runs up and is bolted to the ground lug for the fuel tank which is located under the cabin sole. The fuel tank is approximately 3'wide x 6'long. It then runs under the starboard settee, through a bulkhead and into a small hanging locker under the Nav station. The entire run is one piece and is covered with epoxy and fiberglass tape to protect it. Also, there is several extra feet of foil coiled on each end for attaching the antenna tuner and radio.
What do you think?
Mike Thorpe
CD-36 Journey's End
Hyannis, MA
Larry DeMers wrote: Your SSB ground is supposed to be a good RF ground, so the testing that would reveal it's quality would involve sendingRF of the frequencies you are interested in over your antenna/ground combination and observing the VSWR returned from the antenna. In short..using it and then measuring the performance while in operation.
One way to scope it out ahead of time is to describe the grounding system precisely to us, and lets see what it consists of. Another would be to use some equipment to measure the reactance of that ground circuit, and see if it is low enough at your operating frequencies, but this requires specialized equipment, like the MFJ antenna analyzer box that Ken talked about last week. This box would output an rf sig. in the freq. range of interest, and would then read the VSWR of that ground. It should be in resonance (SWR of less than 1:1.8) at the freq. you are using.
How about a description of the grounding path?
Cheers,
Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior
ex-K0INX for 30 years
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
demers@sgi.com
-
John R.
Re: Testing SSB Ground????
The laymans way to test it is to hook up the entire radio and antenna tuner and transmit on various frequencies and pay attention to propagation. Make sure your (ground) counterpoise is not led near RF inducing equipment like the engine.
Your described counterpoise sounds just fine and should work well. One thing you might wish to reconsider is the manner of the connections to the seacocks. I would bolt them to the seacock bolts rather than wrapping foil around them and using a clamp (susceptible to corrosion). Fold the foil into several layers and solder it, drill a hole in it and then bolt it onto the seacock stud, use a dielectric grease to prevent corrosion to the connection. Also bolt the foil to the keel ballast, I believe the entire ballast to be lead in the CD, that makes a great counterpoise, encapsulated or not encapsulated ballast. Using it in combination with what you already have will give you a large and powerful counterpoise. You generally need anywhere between 10 and 100 sq ft of total combined counterpoise. The bigger the counterpoise the bigger the push your signal will get.
Check the owners manual of your SSB, it should have a fully detailed description of setting up a proper counterpoise for your system.
Your described counterpoise sounds just fine and should work well. One thing you might wish to reconsider is the manner of the connections to the seacocks. I would bolt them to the seacock bolts rather than wrapping foil around them and using a clamp (susceptible to corrosion). Fold the foil into several layers and solder it, drill a hole in it and then bolt it onto the seacock stud, use a dielectric grease to prevent corrosion to the connection. Also bolt the foil to the keel ballast, I believe the entire ballast to be lead in the CD, that makes a great counterpoise, encapsulated or not encapsulated ballast. Using it in combination with what you already have will give you a large and powerful counterpoise. You generally need anywhere between 10 and 100 sq ft of total combined counterpoise. The bigger the counterpoise the bigger the push your signal will get.
Check the owners manual of your SSB, it should have a fully detailed description of setting up a proper counterpoise for your system.
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
-
Mike Thorpe
Thanks to all
To every one that responded, thank you. It seems that the next step will be to buy the radio and see how it goes. Larry, to answer your question, yes I was planning on buying an automatic antenna tuner with the radio. Right now I'm leaning towards an ICOM SSB/Ham combination. Any thoughts?
Mike
CD-36
Journey's End
Hyannis
mthorpe@capecod.net
Mike
CD-36
Journey's End
Hyannis
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
mthorpe@capecod.net
-
Larry DeMers
Re: Testing SSB Ground????
Well, not quite accurate John.
The reason for a "Counterpoise" or ground reflector is that the ground comprises 1/2 of the antenna at your chosen frequency. It has a built in limit as to how much it will help with your output, so simply increasing the physical size of the lump of grounding material will not affect the signal strength in any way. If the ground is a sufficient ground, that is as good as it gets, and adding a ton more of grounding metal will not improve the signal once the rf 'sees' a low impedance image of it's antenna in the ground.
Of much higher importance is the length of the ground cable from the transciever to the primary grounding point (contact with water). This MUST be as short as possible, of a low inductance design, and it MUST have a low impedance connection at both ends, as you wisely pointed out. Your connection idea with the dielectric grease to prevent corrosion is a good one too.
Now, how do you suggest even accessing the lead keel on our CD30's or any other CD?? These are encapsulated keels as you know. So the metal itself is not exposed as far as I have seen so far..if it is..where??
There has been a series of good experiments done on this very topic, by someone you probalby will listen to (obviously not me). Gordon West I believe did some experiments that started out using just the thru-hulls for a ground on his SSB and Ham rigs. Signal reports were taken on his signal strength and quality, then he changed the ground scheme to use a trailing (in the water) piece of copper mesh along with the thru hulls..no improvement in sig strength. Then he added other underwater metal, and again no improvement in sig. reports.
While this is far from scientific, and certainly not very exhaustive of a study, it points out that grounding is NOT a cookie-cutter practice. You simply will not be able to just do this..then that, and everything will be fine. Believe it or not, someone who is trying to make their sigs as good as they can be will actually need to read some technical articles and understand some of that technical jargon that you dislike so much. But of course, that is expected by most folks since this is a technical undertaking.
Now to your article:
Buying the proper test equipment will accomplish this work in a matter of minutes. "Layman's way"...what does this mean? If you are using Ham or SSB, it is Assummed that you are a technically proficient person who knows enough to tune and properly operate the equipment,thus taking you out of the layman category. So a 'layman' has no business installing or operating these radios.
The more **EDGE** of a given conductor you have exposed to seawater, the better the grounding up to it's maximum possible coupling. That is why the sintered RF ground is so good at these frequencies. Many, many edges in that plate, giving a good rf ground, usually in conjunction with other grounds on the boat.
Cheers,
Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior
demers@sgi.com
The reason for a "Counterpoise" or ground reflector is that the ground comprises 1/2 of the antenna at your chosen frequency. It has a built in limit as to how much it will help with your output, so simply increasing the physical size of the lump of grounding material will not affect the signal strength in any way. If the ground is a sufficient ground, that is as good as it gets, and adding a ton more of grounding metal will not improve the signal once the rf 'sees' a low impedance image of it's antenna in the ground.
Of much higher importance is the length of the ground cable from the transciever to the primary grounding point (contact with water). This MUST be as short as possible, of a low inductance design, and it MUST have a low impedance connection at both ends, as you wisely pointed out. Your connection idea with the dielectric grease to prevent corrosion is a good one too.
Now, how do you suggest even accessing the lead keel on our CD30's or any other CD?? These are encapsulated keels as you know. So the metal itself is not exposed as far as I have seen so far..if it is..where??
There has been a series of good experiments done on this very topic, by someone you probalby will listen to (obviously not me). Gordon West I believe did some experiments that started out using just the thru-hulls for a ground on his SSB and Ham rigs. Signal reports were taken on his signal strength and quality, then he changed the ground scheme to use a trailing (in the water) piece of copper mesh along with the thru hulls..no improvement in sig strength. Then he added other underwater metal, and again no improvement in sig. reports.
While this is far from scientific, and certainly not very exhaustive of a study, it points out that grounding is NOT a cookie-cutter practice. You simply will not be able to just do this..then that, and everything will be fine. Believe it or not, someone who is trying to make their sigs as good as they can be will actually need to read some technical articles and understand some of that technical jargon that you dislike so much. But of course, that is expected by most folks since this is a technical undertaking.
Now to your article:
This method will tell you if the rig is running, and that is about all, unless you spend months in each successive step of your tuning, and even then, how will you know the difference between your better ground that you spent the last month working on vs. better proagation due to the sun spot cycle just peaking.John R. wrote: The laymans way to test it is to hook up the entire radio and antenna tuner and transmit on various frequencies and pay attention to propagation.
Buying the proper test equipment will accomplish this work in a matter of minutes. "Layman's way"...what does this mean? If you are using Ham or SSB, it is Assummed that you are a technically proficient person who knows enough to tune and properly operate the equipment,thus taking you out of the layman category. So a 'layman' has no business installing or operating these radios.
Diesel engines themselves are quite quiet RF wise. The alternator will generate noise though, so staying away from the output cable would seem wise, but this noise travels, so your efforts would be better spent routing the counterpoise wiring as directly as possible to the grounding point on the boat (usually a sintered plate on the exterior).John R. wrote: Make sure your (ground) counterpoise is not led near RF inducing equipment like the engine.
Good advice here folks. This is a good method to use.John R. wrote: Your described counterpoise sounds just fine and should work well. One thing you might wish to reconsider is the manner of the connections to the seacocks. I would bolt them to the seacock bolts rather than wrapping foil around them and using a clamp (susceptible to corrosion). Fold the foil into several layers and solder it, drill a hole in it and then bolt it onto the seacock stud, use a dielectric grease to prevent corrosion to the connection.
Not sure how to access the ballast on the CD's as they do not have bolts to hold them onto the boat..the lead is in the form of pigs that are layed in and fiberglassed over. So how to attach? I suspect that this is more work than anything, and will result in little increase in the signal strength or quality -if the ground is proper in all other aspects.John R. wrote: Also bolt the foil to the keel ballast, I believe the entire ballast to be lead in the CD, that makes a great counterpoise, encapsulated or not encapsulated ballast.
That is a 10:1 variance...so anything will work? Nope.John R. wrote: Using it in combination with what you already have will give you a large and powerful counterpoise. You generally need anywhere between 10 and 100 sq ft of total combined counterpoise.
The more **EDGE** of a given conductor you have exposed to seawater, the better the grounding up to it's maximum possible coupling. That is why the sintered RF ground is so good at these frequencies. Many, many edges in that plate, giving a good rf ground, usually in conjunction with other grounds on the boat.
Not true. There is a rock wall limit where more counterpoise will not increase sig. strength. More is not always better.John R. wrote: The bigger the counterpoise the bigger the push your signal will get.
Yup..good advice here. I might also add that there are innumerable books out there that will also give you a tutorial on grounding, SSB comms, theory and practices. These are all needed in order to get the most of your radio.John R. wrote: Check the owners manual of your SSB, it should have a fully detailed description of setting up a proper counterpoise for your system.
Cheers,
Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior
John R. wrote:Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
demers@sgi.com
-
Larry DeMers
Re: Thanks to all
Mike,
Yes..do so!! heh. Mount that auto-tuner as close to the antenna base as possible. Ground the tuner as directed..exactly, with no short cuts. Provide oversize DC cable to the tuner and use a large ferrite bead on the power wiring to keep the rf out of the DC distribution system, which would get into your nav gear, autopilot etc.
These tuners are able to quickly an accurately tune most antennas to the radio, and usually are quite trouble free.
If you want to, shoot me whatever Q's you come up with after buying the gear, and I'll do what I can to help you get it installed right.
Cheers,
Larry Demers
s/v DeLaMer
Cape Dory 30 Lake Superior
demers@sgi.com
Yes..do so!! heh. Mount that auto-tuner as close to the antenna base as possible. Ground the tuner as directed..exactly, with no short cuts. Provide oversize DC cable to the tuner and use a large ferrite bead on the power wiring to keep the rf out of the DC distribution system, which would get into your nav gear, autopilot etc.
These tuners are able to quickly an accurately tune most antennas to the radio, and usually are quite trouble free.
If you want to, shoot me whatever Q's you come up with after buying the gear, and I'll do what I can to help you get it installed right.
Cheers,
Larry Demers
s/v DeLaMer
Cape Dory 30 Lake Superior
Mike Thorpe wrote: To every one that responded, thank you. It seems that the next step will be to buy the radio and see how it goes. Larry, to answer your question, yes I was planning on buying an automatic antenna tuner with the radio. Right now I'm leaning towards an ICOM SSB/Ham combination. Any thoughts?
Mike
CD-36
Journey's End
Hyannis
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
demers@sgi.com
-
Ken Coit
Lead Pigs in a Blanket
If anyone knows how to access the lead ballast on a 36, I wish they would share it so I can hook up my RF ground. How far below the cap is the lead? Could we drill into it, provide a bolt for connection and then reseal? Are the lead pigs connected or insulated from one another?
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
parfaitNOSPAM@nc.rr.com
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
parfaitNOSPAM@nc.rr.com
-
Ken Coit
Re: Thanks to all
Mike,
From what has been posted here about HF gear and what I have read on the relevant ham boards, Icom is the way to go. Kenwood's ham gear and their customer service are being bashed heavily and Yaeseu is somewhere in the middle. The other marine SSB vendors seem to have a problem with frequency stability that makes it difficult to work email systems.
Check out Dockyard Electrics http://www.dockyardelectrics.com/icom_ssb.htm
for competitive prices on gear.
Farallon might also have a deal for you.
http://www.yachtwire.com
You might find their article on HF for boats a good read:
http://www.yachtwire.com/ssb.pdf
I think I saw a 710 on ebay for $1400 Buy Now.
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
parfaitNOSPAM@nc.rr.com
From what has been posted here about HF gear and what I have read on the relevant ham boards, Icom is the way to go. Kenwood's ham gear and their customer service are being bashed heavily and Yaeseu is somewhere in the middle. The other marine SSB vendors seem to have a problem with frequency stability that makes it difficult to work email systems.
Check out Dockyard Electrics http://www.dockyardelectrics.com/icom_ssb.htm
for competitive prices on gear.
Farallon might also have a deal for you.
http://www.yachtwire.com
You might find their article on HF for boats a good read:
http://www.yachtwire.com/ssb.pdf
I think I saw a 710 on ebay for $1400 Buy Now.
Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
Mike Thorpe wrote: To every one that responded, thank you. It seems that the next step will be to buy the radio and see how it goes. Larry, to answer your question, yes I was planning on buying an automatic antenna tuner with the radio. Right now I'm leaning towards an ICOM SSB/Ham combination. Any thoughts?
Mike
CD-36
Journey's End
Hyannis
Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
parfaitNOSPAM@nc.rr.com
-
John R.
Re: Testing SSB Ground????
Look Larry,
I think the cat is out of the bag, I know you are on Lake *Superior* but quite frankly I never thought I would have to make this statement as I've tried hard to restrain for the good of the board and my own self respect as a just member of the board. You know darned well the validity of the points I made in the last post. I frankly am not interested in taking basic practical points and hashing them to the point of engineering theory and death. You obviously are interested in that and it is your right to pursue. I think matters are better discussed on a level that most readers can fully understand and advice be kept in line with common recreational marine practice. I respectfully submit that most readers on this board are not interested in the engineering level of discussion or argument. I'm sure you know full well that the SSB counterpoise outline I mentioned are common practice in the marine industry and have been for years, it is not *law* but it is a fundamentally accepted practice and can easily be verified by a multitude of respected texts including manufacturers manuals. If you wish to make virtually the entire post seem invalid because it does not meet your criteria for discussion then you are doing a disservice to all readers. If you truly know about the marine industry, then you know this full well to be true. I submit that you prefer to manipulate an issue beyond practicality so that you ultimately carry the crown. Whenever I have found myself entangled in a lenthly thread of debate with you it is most always because a concerted effort has been sought to unearth a generality in my remarks that you feel needs to be embellished with discussion to the point of absurdity. I am not interested in playing that ego game. My remarks speak for themselves and are well founded from over 20 years experience specifically in the marine industry here in Florida. If that experience doesn't meet your threshold then I bow to Lake *Superior*. There is simply no just reason to try and destroy my comments and ideas each and every time unless you simply do not like me. I believe that is the basis. How terrible it is to have to make that statement on this fine board, but the time has come to face the simple facts.
With that said.... you are entitled to respond to my future post contributions on this board as you know you have the right to do but never expect another dialog from me over your continually inflated points which seem to me to be a conscious effort to undermine and initiate argument.
I state to all readers of my posts past and present that information I have posted to this board can be verified as common techniques employed in professional marine services. Naturally any topic can be taken to a theoretical and engineering level beyond the scope of the layman reader that visits and participates on this board but my posts are initially never intended to introduce such complexity. For the benefit of everyone (including saving time for myself)I try to keep the remarks as simple and direct as possible but on many occassions I find my points being dragged into a totally unneccessary escalation of the issue beyond practical limits by Mr. Demers. That of course is his right but I don't appreciate blatant intent to purposely distort my points which seem to be all to frequent in his replies. Not to mention the occassional obvious, but sly, personal insults to myself and my friends (coax post of a few days ago).
This response by me is not specific to this latest posting by Larry but is a statement based on a culmination of events that have been issued by Larry over the past many months.
Larry, I will not dialog with you on any future topics including a response to this SSB thread for the mere reason of looking out for the health of this board. This board has been under enough personal upheavel of late and it is sad I have been forced to become an element of that. I hope you will take it upon yourself to reciprocate from responding to my posts to avoid these types of problems in the future. As you fully know you certainly do have the right to post responses to my posts based on the bylaws of the board but please don't, I'm sick of it.
Regarding this SSB post and my decision not to respond to your initiated thread; leave it to say that readers interested in this topic should consult available marine texts that have been fully researched as to common practices adopted throughout the marine industry on SSB installations.
I apologize to the board participants and Walt and Catherine for having to publicly make this statement on this fine board. It was the last thing I ever wanted to do but have been driven to this point by Mr. Demers.
Sorry everyone!
I think the cat is out of the bag, I know you are on Lake *Superior* but quite frankly I never thought I would have to make this statement as I've tried hard to restrain for the good of the board and my own self respect as a just member of the board. You know darned well the validity of the points I made in the last post. I frankly am not interested in taking basic practical points and hashing them to the point of engineering theory and death. You obviously are interested in that and it is your right to pursue. I think matters are better discussed on a level that most readers can fully understand and advice be kept in line with common recreational marine practice. I respectfully submit that most readers on this board are not interested in the engineering level of discussion or argument. I'm sure you know full well that the SSB counterpoise outline I mentioned are common practice in the marine industry and have been for years, it is not *law* but it is a fundamentally accepted practice and can easily be verified by a multitude of respected texts including manufacturers manuals. If you wish to make virtually the entire post seem invalid because it does not meet your criteria for discussion then you are doing a disservice to all readers. If you truly know about the marine industry, then you know this full well to be true. I submit that you prefer to manipulate an issue beyond practicality so that you ultimately carry the crown. Whenever I have found myself entangled in a lenthly thread of debate with you it is most always because a concerted effort has been sought to unearth a generality in my remarks that you feel needs to be embellished with discussion to the point of absurdity. I am not interested in playing that ego game. My remarks speak for themselves and are well founded from over 20 years experience specifically in the marine industry here in Florida. If that experience doesn't meet your threshold then I bow to Lake *Superior*. There is simply no just reason to try and destroy my comments and ideas each and every time unless you simply do not like me. I believe that is the basis. How terrible it is to have to make that statement on this fine board, but the time has come to face the simple facts.
With that said.... you are entitled to respond to my future post contributions on this board as you know you have the right to do but never expect another dialog from me over your continually inflated points which seem to me to be a conscious effort to undermine and initiate argument.
I state to all readers of my posts past and present that information I have posted to this board can be verified as common techniques employed in professional marine services. Naturally any topic can be taken to a theoretical and engineering level beyond the scope of the layman reader that visits and participates on this board but my posts are initially never intended to introduce such complexity. For the benefit of everyone (including saving time for myself)I try to keep the remarks as simple and direct as possible but on many occassions I find my points being dragged into a totally unneccessary escalation of the issue beyond practical limits by Mr. Demers. That of course is his right but I don't appreciate blatant intent to purposely distort my points which seem to be all to frequent in his replies. Not to mention the occassional obvious, but sly, personal insults to myself and my friends (coax post of a few days ago).
This response by me is not specific to this latest posting by Larry but is a statement based on a culmination of events that have been issued by Larry over the past many months.
Larry, I will not dialog with you on any future topics including a response to this SSB thread for the mere reason of looking out for the health of this board. This board has been under enough personal upheavel of late and it is sad I have been forced to become an element of that. I hope you will take it upon yourself to reciprocate from responding to my posts to avoid these types of problems in the future. As you fully know you certainly do have the right to post responses to my posts based on the bylaws of the board but please don't, I'm sick of it.
Regarding this SSB post and my decision not to respond to your initiated thread; leave it to say that readers interested in this topic should consult available marine texts that have been fully researched as to common practices adopted throughout the marine industry on SSB installations.
I apologize to the board participants and Walt and Catherine for having to publicly make this statement on this fine board. It was the last thing I ever wanted to do but have been driven to this point by Mr. Demers.
Sorry everyone!
Larry DeMers wrote: Well, not quite accurate John.
The reason for a "Counterpoise" or ground reflector is that the ground comprises 1/2 of the antenna at your chosen frequency. It has a built in limit as to how much it will help with your output, so simply increasing the physical size of the lump of grounding material will not affect the signal strength in any way. If the ground is a sufficient ground, that is as good as it gets, and adding a ton more of grounding metal will not improve the signal once the rf 'sees' a low impedance image of it's antenna in the ground.
Of much higher importance is the length of the ground cable from the transciever to the primary grounding point (contact with water). This MUST be as short as possible, of a low inductance design, and it MUST have a low impedance connection at both ends, as you wisely pointed out. Your connection idea with the dielectric grease to prevent corrosion is a good one too.
Now, how do you suggest even accessing the lead keel on our CD30's or any other CD?? These are encapsulated keels as you know. So the metal itself is not exposed as far as I have seen so far..if it is..where??
There has been a series of good experiments done on this very topic, by someone you probalby will listen to (obviously not me). Gordon West I believe did some experiments that started out using just the thru-hulls for a ground on his SSB and Ham rigs. Signal reports were taken on his signal strength and quality, then he changed the ground scheme to use a trailing (in the water) piece of copper mesh along with the thru hulls..no improvement in sig strength. Then he added other underwater metal, and again no improvement in sig. reports.
While this is far from scientific, and certainly not very exhaustive of a study, it points out that grounding is NOT a cookie-cutter practice. You simply will not be able to just do this..then that, and everything will be fine. Believe it or not, someone who is trying to make their sigs as good as they can be will actually need to read some technical articles and understand some of that technical jargon that you dislike so much. But of course, that is expected by most folks since this is a technical undertaking.
Now to your article:
This method will tell you if the rig is running, and that is about all, unless you spend months in each successive step of your tuning, and even then, how will you know the difference between your better ground that you spent the last month working on vs. better proagation due to the sun spot cycle just peaking.John R. wrote: The laymans way to test it is to hook up the entire radio and antenna tuner and transmit on various frequencies and pay attention to propagation.
Buying the proper test equipment will accomplish this work in a matter of minutes. "Layman's way"...what does this mean? If you are using Ham or SSB, it is Assummed that you are a technically proficient person who knows enough to tune and properly operate the equipment,thus taking you out of the layman category. So a 'layman' has no business installing or operating these radios.
Diesel engines themselves are quite quiet RF wise. The alternator will generate noise though, so staying away from the output cable would seem wise, but this noise travels, so your efforts would be better spent routing the counterpoise wiring as directly as possible to the grounding point on the boat (usually a sintered plate on the exterior).John R. wrote: Make sure your (ground) counterpoise is not led near RF inducing equipment like the engine.
Good advice here folks. This is a good method to use.John R. wrote: Your described counterpoise sounds just fine and should work well. One thing you might wish to reconsider is the manner of the connections to the seacocks. I would bolt them to the seacock bolts rather than wrapping foil around them and using a clamp (susceptible to corrosion). Fold the foil into several layers and solder it, drill a hole in it and then bolt it onto the seacock stud, use a dielectric grease to prevent corrosion to the connection.
Not sure how to access the ballast on the CD's as they do not have bolts to hold them onto the boat..the lead is in the form of pigs that are layed in and fiberglassed over. So how to attach? I suspect that this is more work than anything, and will result in little increase in the signal strength or quality -if the ground is proper in all other aspects.John R. wrote: Also bolt the foil to the keel ballast, I believe the entire ballast to be lead in the CD, that makes a great counterpoise, encapsulated or not encapsulated ballast.
That is a 10:1 variance...so anything will work? Nope.John R. wrote: Using it in combination with what you already have will give you a large and powerful counterpoise. You generally need anywhere between 10 and 100 sq ft of total combined counterpoise.
The more **EDGE** of a given conductor you have exposed to seawater, the better the grounding up to it's maximum possible coupling. That is why the sintered RF ground is so good at these frequencies. Many, many edges in that plate, giving a good rf ground, usually in conjunction with other grounds on the boat.
Not true. There is a rock wall limit where more counterpoise will not increase sig. strength. More is not always better.John R. wrote: The bigger the counterpoise the bigger the push your signal will get.
Yup..good advice here. I might also add that there are innumerable books out there that will also give you a tutorial on grounding, SSB comms, theory and practices. These are all needed in order to get the most of your radio.John R. wrote: Check the owners manual of your SSB, it should have a fully detailed description of setting up a proper counterpoise for your system.
Cheers,
Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior
John R. wrote:Mike Thorpe wrote: Is there any way to test the SSB ground in my CD-36 short of attaching a SSB radio to it and seeing what happens?
I'm asking because last winter, in anticipation of installing a SSB Radio this winter, I included insulators when I had the backstay replaced and installed what I think is a good SSB ground.
Now it occurs to me, how can I be sure if the ground is any good?
Anyone have any suggestions on how I can test it?
Mike Thorpe
CD-36
Journey's End
-
John R.
Re: Lead Pigs in a Blanket
Yes Ken, I did so on my CD30. I simply drilled and installed a bronze bolt stud. Took two attempts with a pilot bit before hitting lead.
If anyone knows how to access the lead ballast on a 36, I wish they would share it so I can hook up my RF ground. How far below the cap is the lead? Could we drill into it, provide a bolt for connection and then reseal? Are the lead pigs connected or insulated from one another?
If anyone knows how to access the lead ballast on a 36, I wish they would share it so I can hook up my RF ground. How far below the cap is the lead? Could we drill into it, provide a bolt for connection and then reseal? Are the lead pigs connected or insulated from one another?
Ken Coit wrote: Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
-
Ken Coit
Re: Lead Pigs in a Blanket
John,
How thick is the covering resin?
Thanks,
Ken
parfaitNOSPAM@nc.rr.com
How thick is the covering resin?
Thanks,
Ken
John R. wrote: Yes Ken, I did so on my CD30. I simply drilled and installed a bronze bolt stud. Took two attempts with a pilot bit before hitting lead.
If anyone knows how to access the lead ballast on a 36, I wish they would share it so I can hook up my RF ground. How far below the cap is the lead? Could we drill into it, provide a bolt for connection and then reseal? Are the lead pigs connected or insulated from one another?
Ken Coit wrote: Keep on sailing,
Ken Coit, ND7N
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC
parfaitNOSPAM@nc.rr.com