The KISS SSB Counterpoise - Revealed ( with Pics )

[CAELESTIS]

Test complete. I have a Kiss, and recently ran 25' of copper strap to the nearest thru hull that remains permanently submerged.
While in Mexico, I ran a few tests. They were not formal. My radio was better with the KISS than the copper strap. Practice your voodoo, read your 1950's books, I don't care. KISS is better.

[SoonerSailor]

There you have it! Case closed! Thank you very much Calestis. Imagine our relief!

By the way, the Answer to the Ultimate Question of Life, the Universe, and Everything is 42. So we can stop arguing about that one too.

Plebian is correct in that knowing ground loss would be very useful, but I haven't come across a good way to make such a measurement myself.

[s/v Jedi]

@Plebian99: you lost it man. You act like if you have the answer and it's all so simple, but you fail to realize how many bands must be supported and that we use automatic couplers that insert matching networks with thousands of possibilities and all of those multiplied by all possible frequencies, are variables in your simple ground loss equation. There are several members here that have done (or still do) professional RF engineering and it is obvious that you do not have the knowledge to match your long posts.

[plebian99]

No I have not lost it. I just see the big picture and I refuse to be a expert that has a magic pudding recipe for every sailors SSB ground problem. I dont know what antenna matching has got to do with fixing up ground loss or providing a ground system? Well if the expert panel of RF ENGINEERS cant tell you what the ground loss figure is, they are not very good RF engineer or whatever their esteemed expert status is. Let me put it this in simple terms for you. If you powered a light globe through 1 mile of cable and the globe did not light up. You would ask the question why no voltage or current is getting to the light globe. You would pull your calculator or wire cable table and figure that your cable is way to small and has too much loss. A multimeter would even give you the answer as well. RF ground loss over seawater is exactly the same problem of loss. The only difference is that you trying to combat this loss from a radiated RF field. Now a BASIC and very simple point is this. If you dont know what your RF ground loss is, how can arrogantly go around being a SSB expert making recommendations for a problem that you cant measure or quantify! So here you have experts who cant tell you the ground loss figure and then cant measure what they are trying to fix and you call them experts?Thats the problem here with all these SSB debates, you have a lot of radio experts who seem to have all the answers but dont even understand the basics of the problem. I suppose thats why if you read the many sailing forums we have the same people going around on the merry go round for years promoting their SSB expert status and recommending magic pudding recipes for SSB ground system. Guess what, there are thousands of SSB installations that are working fine without their input, and why they work is that the experts dont know what they are trying to fix. Imagine that an installer flips a coin and plugs in a SSB radio and it works. WOW, does all these installers have divine expert SSB status, did they get luck or is ground loss so small most people cant notice it? What is the answer? What the experts should address is what the ground loss resistance is, and when they understand this they will be able to fully understand how their magic recipe ground systems behave and work when installed on a yacht. Since they have no measured data or numbers everything that they say is just anecdotal generalized information that is mostly applicable to their boat alone. So, to make this clear for yourself. We not talking about antenna tuner losses or matching losses we talking about how a ground system makes an antenna work or combats the RF ground loss which improves your signal. Its school kid maths. Since the experts cant quantify this loss figure they have no idea what they are trying to accomplish when installing a RF ground system. Maybe you can clear all this up for me. I am not a great RF Engineer like yourself who has a deeper understanding of these issues. Maybe you can enlighten me and tell me what the ground loss is for a typical sailing yacht over seawater? When you tell me that I will at least know how to go about installing a ground system that will combat this loss. Man this is so simple, I wasted so many words on such a simple problem. All we know is that we must have a RFground. What we dont know is what the ground loss figure is and therefor how big a ground system should be installed to combat these losses. If their is no ground loss then you still need a bare minimum RFground to make the antenna work and to combat things like RF feedback. I would appreciate you technical input to help me resolve my non engineering understanding of this simple problem. Thanks!

Originally Posted by s/v Jedi

@Plebian99: you lost it man. You act like if you have the answer and it's all so simple, but you fail to realize how many bands must be supported and that we use automatic couplers that insert matching networks with thousands of possibilities and all of those multiplied by all possible frequencies, are variables in your simple ground loss equation. There are several members here that have done (or still do) professional RF engineering and it is obvious that you do not have the knowledge to match your long posts.

[s/v Jedi]

Originally Posted by plebian99

No I have not lost it. I just see the big picture and I refuse to be a expert that has a magic pudding recipe for every sailors SSB ground problem. I dont know what antenna matching has got to do with fixing up ground loss or providing a ground system? Well if the expert panel of RF ENGINEERS cant tell you what the ground loss figure is, they are not very good RF engineer or whatever their esteemed expert status is. Let me put it this in simple terms for you. If you powered a light globe through 1 mile of cable and the globe did not light up. You would ask the question why no voltage or current is getting to the light globe. You would pull your calculator or wire cable table and figure that your cable is way to small and has too much loss. A multimeter would even give you the answer as well. RF ground loss over seawater is exactly the same problem of loss. The only difference is that you trying to combat this loss from a radiated RF field. Now a BASIC and very simple point is this. If you dont know what your RF ground loss is, how can arrogantly go around being a SSB expert making recommendations for a problem that you cant measure or quantify! So here you have experts who cant tell you the ground loss figure and then cant measure what they are trying to fix and you call them experts?Thats the problem here with all these SSB debates, you have a lot of radio experts who seem to have all the answers but dont even understand the basics of the problem. I suppose thats why if you read the many sailing forums we have the same people going around on the merry go round for years promoting their SSB expert status and recommending magic pudding recipes for SSB ground system. Guess what, there are thousands of SSB installations that are working fine without their input, and why they work is that the experts dont know what they are trying to fix. Imagine that an installer flips a coin and plugs in a SSB radio and it works. WOW, does all these installers have divine expert SSB status, did they get luck or is ground loss so small most people cant notice it? What is the answer? What the experts should address is what the ground loss resistance is, and when they understand this they will be able to fully understand how their magic recipe ground systems behave and work when installed on a yacht. Since they have no measured data or numbers everything that they say is just anecdotal generalized information that is mostly applicable to their boat alone. So, to make this clear for yourself. We not talking about antenna tuner losses or matching losses we talking about how a ground system makes an antenna work or combats the RF ground loss which improves your signal. Its school kid maths. Since the experts cant quantify this loss figure they have no idea what they are trying to accomplish when installing a RF ground system. Maybe you can clear all this up for me. I am not a great RF Engineer like yourself who has a deeper understanding of these issues. Maybe you can enlighten me and tell me what the ground loss is for a typical sailing yacht over seawater? When you tell me that I will at least know how to go about installing a ground system that will combat this loss. Man this is so simple, I wasted so many words on such a simple problem. All we know is that we must have a RFground. What we dont know is what the ground loss figure is and therefor how big a ground system should be installed to combat these losses. If their is no ground loss then you still need a bare minimum RFground to make the antenna work and to combat things like RF feedback. I would appreciate you technical input to help me resolve my non engineering understanding of this simple problem. Thanks!

If you're talking to me and expecting an answer, you'll have to post something that I can read first, not the blurr of nonsense like above. A couple of years of RF engineering study might help too. Your "big picture" that you see and understand so well, exists only in your fantasy.

[kaimusailing]

Ahoy s/v Jedi,
+1

[transmitterdan]

Originally Posted by plebian99

What is the answer?

Forty Two?

[CAELESTIS]

Originally Posted by transmitterdan

Forty Two?

WTF.com. Funny. Don't know why this is such a big deal. Either it works or it doesn't. My 1950 text book says . . .

[Viking Sailor]

Originally Posted by plebian99

No I have not lost it. I just see the big picture and I refuse to be a expert that has a magic pudding recipe for every sailors SSB ground problem. I dont know what antenna matching has got to do with fixing up ground loss or providing a ground system? Well if the expert panel of RF ENGINEERS cant tell you what the ground loss figure is, they are not very good RF engineer or whatever their esteemed expert status is. Let me put it this in simple terms for you. If you powered a light globe through 1 mile of cable and the globe did not light up. You would ask the question why no voltage or current is getting to the light globe. You would pull your calculator or wire cable table and figure that your cable is way to small and has too much loss. A multimeter would even give you the answer as well. RF ground loss over seawater is exactly the same problem of loss. The only difference is that you trying to combat this loss from a radiated RF field. Now a BASIC and very simple point is this. If you dont know what your RF ground loss is, how can arrogantly go around being a SSB expert making recommendations for a problem that you cant measure or quantify! So here you have experts who cant tell you the ground loss figure and then cant measure what they are trying to fix and you call them experts?Thats the problem here with all these SSB debates, you have a lot of radio experts who seem to have all the answers but dont even understand the basics of the problem. I suppose thats why if you read the many sailing forums we have the same people going around on the merry go round for years promoting their SSB expert status and recommending magic pudding recipes for SSB ground system. Guess what, there are thousands of SSB installations that are working fine without their input, and why they work is that the experts dont know what they are trying to fix. Imagine that an installer flips a coin and plugs in a SSB radio and it works. WOW, does all these installers have divine expert SSB status, did they get luck or is ground loss so small most people cant notice it? What is the answer? What the experts should address is what the ground loss resistance is, and when they understand this they will be able to fully understand how their magic recipe ground systems behave and work when installed on a yacht. Since they have no measured data or numbers everything that they say is just anecdotal generalized information that is mostly applicable to their boat alone. So, to make this clear for yourself. We not talking about antenna tuner losses or matching losses we talking about how a ground system makes an antenna work or combats the RF ground loss which improves your signal. Its school kid maths. Since the experts cant quantify this loss figure they have no idea what they are trying to accomplish when installing a RF ground system. Maybe you can clear all this up for me. I am not a great RF Engineer like yourself who has a deeper understanding of these issues. Maybe you can enlighten me and tell me what the ground loss is for a typical sailing yacht over seawater? When you tell me that I will at least know how to go about installing a ground system that will combat this loss. Man this is so simple, I wasted so many words on such a simple problem. All we know is that we must have a RFground. What we dont know is what the ground loss figure is and therefor how big a ground system should be installed to combat these losses. If their is no ground loss then you still need a bare minimum RFground to make the antenna work and to combat things like RF feedback. I would appreciate you technical input to help me resolve my non engineering understanding of this simple problem. Thanks!

The additional ground resistance needed to reduce the power emitted by a vertical antenna over a near perfect ground (sea water) by X dB's:

Pt = Ia^2 * Rr

Where:

Pt = 100 W (Emitted Dipole Power)
Rr = 72 ohms (Dipole Radiation Resistance)
Ia = 1.1785 A (Antenna Current)

Pv = Rv * Ia^2

Where:

Pv = 50 W (Emitted Vertical Power)
Rv = Rr / 2 = 36 ohms (Vertical Radiation Resistance)

Pn = (Rr - Rv) * Ia^2

Where:

Pn = 50 W (Non-radiated Power)

Pe = Pv - (10^(X/10))

Where:

Pe = 25 W (Effective Radiated Power)
X = 3 dB's (Additional Ground Loss)

Rl = ( (Pt-Pe) / (Pe/Rv) ) - Rv

Where:

Rl = 72 ohms (Additional Ground Loss Resistance)

Thus, it would take an additional 72 ohms of resistance in the ground path to realize a 3 dB signal reduction due to ground loss.

A dipole has a gain of 2.15 dBi in free space and a vertical has a gain of 5.15 dBi over a near perfect ground. The 3 dB difference between the dipole and the vertical makes up for the 50% of the power that is "dumped" into the ground when feeding a vertical.

This gain is due to the reflection of the RF waves by the ground. However, this gain is greatly reduced as the reflectivity of the ground is reduced. These reductions are more significant close to the antenna -- thus, radials can be used to increase the grounds reflectivity near the antenna.

[Paul Elliott]

Originally Posted by Viking Sailor

The additional ground resistance needed to reduce the power emitted by a vertical antenna over a near perfect ground (sea water) by X dB's:
[equations]

I'm not sure about that. For your vertical antenna radiation resistance you are using one-half of the resistance of a half-wave dipole. This should be fairly accurate for a full quarter-wave vertical, but most of the time our backstay antennas aren't quarter-waves. They are often electrically short and and so have a much lower radiation resistance.

So, for a given ground-path resistance the reduction in radiated power may be much greater than you calculate.


And I'm not sure I am following your explanation for the vertical only accepting 1/2 the power of the dipole (but making up for the "loss" with gain in the radiation pattern). This doesn't seem right, but then I'm no antenna engineer.

[transmitterdan]

The extra 3dB gain of a monopole over a dipole is a math sleight of hand. A monopole over perfect ground acts just like a dipole. The difference is that both branches of the dipole radiate half the power. But a monopole over lossless ground radiates all the power from a single branch. So we say it has 3dB more gain than a dipole. But the theoretical power thrown into the air is the same. There is no free lunch.

There is no single value for "ground loss" in a SSB installation. It is different on every frequency. It can even be different on the same frequency if the boom is moved or the auto tuner finds a different match. Mismatch loss also is a significant factor. The KISS guys brag about reducing VSWR but a resistor will reduce VSWR too. Only problem is it doesn't improve the radiated power. But nything will be better than 25 feet of strap to a thru hull. That's almost a dipole with 1/2 the power radiated into the bilge.

The best/simplest ground is a short (1-2 feet) wide strap from the tuner to an always submerged thru-hull with the tuner isolated from the power amp via a unun/choke. Put the tuner close to where the antenna lead wire comes through the deck. These simple ideas work 90% of the time. The reason is they are based on how RF works and not black magic.

[s/v Jedi]

Originally Posted by transmitterdan

There is no single value for "ground loss" in a SSB installation. It is different on every frequency. It can even be different on the same frequency if the boom is moved or the auto tuner finds a different match. Mismatch loss also is a significant factor.

That is what I told him and for a time I thought he got it but look at how he came back to it with his big picture thing a couple of posts back...

[plebian99]

This is not the accepted method of calculating the impact of ground loss resistance on the efficiency of a vertical antenna. It does not agree with the work of Brown,Norton and Abbot et al. There is also a considerable difference in results depending on the frequency range. You need to apply a correction factor for the higher frequencies. As it stands we really know the ground loss resistance of seawater. How you go about calculating its impact on efficiency is rather complicated on the higher frequencies. The point however still remains that the ground system should be scaled to the expected losses and if the antenna even needs a RF current return. The way some people here discuss backstay antennas you seem to get the implication that everyone is running a 1/4 wavelength vertical on every HF frequency and hence the need for a RF ground.

Originally Posted by Viking Sailor

The additional ground resistance needed to reduce the power emitted by a vertical antenna over a near perfect ground (sea water) by X dB's:

Pt = Ia^2 * Rr

Where:

Pt = 100 W (Emitted Dipole Power)
Rr = 72 ohms (Dipole Radiation Resistance)
Ia = 1.1785 A (Antenna Current)

Pv = Rv * Ia^2

Where:

Pv = 50 W (Emitted Vertical Power)
Rv = Rr / 2 = 36 ohms (Vertical Radiation Resistance)

Pn = (Rr - Rv) * Ia^2

Where:

Pn = 50 W (Non-radiated Power)

Pe = Pv - (10^(X/10))

Where:

Pe = 25 W (Effective Radiated Power)
X = 3 dB's (Additional Ground Loss)

Rl = ( (Pt-Pe) / (Pe/Rv) ) - Rv

Where:

Rl = 72 ohms (Additional Ground Loss Resistance)

Thus, it would take an additional 72 ohms of resistance in the ground path to realize a 3 dB signal reduction due to ground loss.

A dipole has a gain of 2.15 dBi in free space and a vertical has a gain of 5.15 dBi over a near perfect ground. The 3 dB difference between the dipole and the vertical makes up for the 50% of the power that is "dumped" into the ground when feeding a vertical.

This gain is due to the reflection of the RF waves by the ground. However, this gain is greatly reduced as the reflectivity of the ground is reduced. These reductions are more significant close to the antenna -- thus, radials can be used to increase the grounds reflectivity near the antenna.

[plebian99]

You trying to win argument with simplistic point scoring over between 1 and 2 ohms depending on the frequency? What dramatic impact on loss is that going to make on your end fed backstay? You going to make up a whopping loss so you can look good in the point scoring? Maybe you can tell us what DX you worked because you had 1 or 2 ohms less ground loss resistance!

Yes it does vary but you really being anal, about 1 or 2 ohms. This does not change the point that a SSB expert would at least size his RFground system to match the expected ground losses. I find it amusing that you pick on me and yet all your magic pudding SSB experts dont even raise the issue of ground loss. You gonna pick their suggestions apart because they measure and know nothing about the subject matter? Maybe you perfer the magic pudding recipe ground system cookbook?

Originally Posted by s/v Jedi

That is what I told him and for a time I thought he got it but look at how he came back to it with his big picture thing a couple of posts back...

[plebian99]

The loss varies by as little as 1 to about 2 ohms across the 1 to 30mhz range. You also have to consider the dielectric constant of the ground medium VS frequency. The point is that you can calculate the overall radiation efficiency very accurately. When you consider the antenna size, ground current density and antenna size we can have very good picture of how the antenna and ground system is performing. This is much better way of going about things that relying on anecdotal mumbo jumbo by well meaning SSB experts who just seem to recycle each others posts. Worst yet is people who measure entirely the wrong thing and then condemns useful but practical ground alternatives.

At the end of the day a real SSB expert would consider all the factors that impact on the SSB installation. Rather than relying on anecdotal opinions that have no basis in science I would prefer to know exactly that what I am doing is useful and achieves the desired objective.

It seems that every other aspect of a yachts performance and its systems is subjected to the most detailed scrutiny. However when it comes to science of HF radio and antennas we must rely on mumbo jumbo and useless urban myth. I wonder how people can so arrogantly dismiss the science especially when they dont even want to try and understand the physics of how a antenna actually works in the real world.

Originally Posted by transmitterdan

The extra 3dB gain of a monopole over a dipole is a math sleight of hand. A monopole over perfect ground acts just like a dipole. The difference is that both branches of the dipole radiate half the power. But a monopole over lossless ground radiates all the power from a single branch. So we say it has 3dB more gain than a dipole. But the theoretical power thrown into the air is the same. There is no free lunch.

There is no single value for "ground loss" in a SSB installation. It is different on every frequency. It can even be different on the same frequency if the boom is moved or the auto tuner finds a different match. Mismatch loss also is a significant factor. The KISS guys brag about reducing VSWR but a resistor will reduce VSWR too. Only problem is it doesn't improve the radiated power. But nything will be better than 25 feet of strap to a thru hull. That's almost a dipole with 1/2 the power radiated into the bilge.

The best/simplest ground is a short (1-2 feet) wide strap from the tuner to an always submerged thru-hull with the tuner isolated from the power amp via a unun/choke. Put the tuner close to where the antenna lead wire comes through the deck. These simple ideas work 90% of the time. The reason is they are based on how RF works and not black magic.