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Old 24-05-2013, 13:39   #166
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

Dave,
This has been mentioned often over the years....
Quote:
Originally Posted by goboatingnow View Post
why not use a wide braid, more robust, plenty of 'skin' area
Unfortunately:
a) open "braid" is not very effective, long-term, for RF use (particularly in RF transmission circuits)....
Solid copper wire, solid copper strap, or hollow copper tubing are all acceptable for RF transmission circuits....but not "braid" (although you DO see it used in mediocre designs, it is NOT proper RF engineering...)

b) Bare copper braid would fall apart rapidly on a boat...

c) Even open "tinned braid" would have RF connections issues....and would eventually fail mechanically as well...


Sorry to say this, but if you can't use flat copper strapping, you'd be better using round copper wire.....
I do not recommend use of open copper braid for RF connections....and never on a boat!!!


Fair winds..

John
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Old 24-05-2013, 13:47   #167
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

Mark,
You may have missed the lengthy real-world discussion from last year on the SSCA Disc Boards, where I included my detailed testing and spec analyzer traces....
Quote:
Originally Posted by colemj View Post
This is the first real detailed and extensive experimental methodology I have seen for the KISS. The previous stuff was much more simpler comparisons and theory debates. I could have missed previous experiments like Rick's, though.
Have a look here...
SSCA Forum • View topic - KISS-SSB Counterpoise
SSCA Forum • View topic - KISS-SSB Counterpoise

And, if you have the time to read the whole discussion (which I recommend highly!), from the very beginning....
SSCA Forum • View topic - KISS-SSB Counterpoise



Fair winds...

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Old 24-05-2013, 14:19   #168
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

Quote:
Originally Posted by SeaBuffalo View Post
If someone wants to do a simple install a KISS ground is ok.
I'm getting the impression from the actual testing that it would be simpler and just as good to forgo the KISS, or any counterpoise, entirely.

Doesn't sound like either is a smart idea, though.

Mark
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Old 24-05-2013, 14:21   #169
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

Roy,
You've gotten some good advise here...
If I can be of further assistance, please let me know...



'til then, here are a few tips...
1) A short (< 8' long) run of wide (3" - 6" wide) copper strapping (at least 0.012" thick), from your remote tuner ground lug to the nearest underwater metal connection / bronze thru-hull / Dynaplate, will give you a great RF ground / counterpoise....
Paint the copper strapping (except for the ends where you make the connections) and it will last a LONG time...think decades...

Take Mark's advice to heart....
Quote:
I favor start simple and improve as needed from there. I would run a copper strap to the nearest seacock
Unfortunately all my thru-hulls are Marelon, so I installed two huge/giant Dynaplates ($$$).....but if you've got bronze thru-hulls, and have one within 8' - 10' of your tuner's location, go for it!!


Use of a bronze thru-hull for a direct sea water connection RF ground / counterpoise should not cause any electrolysis problems.....
ALL SGC tuners and all new (last couple years) Icom tuners have DC Blocking caps inside them on the ground connection....so you should have no DC ground issues and no electrolysis issues....




2) Read over some of the threads on the SSCA Disc Board as well...
Lots of experienced / learned input there!!


3) Ask questions...


4) Have a look at Georgia Copper's pages....
VERY informative as well as good prices....
GEORGIA COPPER - Copper ground strap
GEORGIA COPPER - Copper ground strap
GEORGIA COPPER - Comparison of Braid, Strap, Wire



5) Forget the copper mesh....unless you sail a Hinckley (where they installed and soldered-in copper sheeting, in the hull upon lay-up)....or a Dashew-designed/built boat (where they installed copper mesh/screen in the hull upon construction), trying to arrange / design / install copper mesh / sheeting is a BIG waste of time and money!!!
Trust me on this!!!
There is NO need for you to worry about trying to install copper mesh / sheeting....



6) Please accept that there is NO dark art about any of this...
It is science...plain and simple....capable of being tested and proved...
Although, there are some who profit from promulgating the myth that this is some how a "dark art", it just isn't so!!!

Again this should not be a cloudy or murky mess for anyone....it's pretty cut 'n dried science...just cut thru all the marketing crap, and you'll be fine!!!


7) Lightning grounds on boats (and "lightning protection" on boats) is a whoie 'nother discussion.....and better suited for a new thread, where you can delve into the "dark art" of lightning.... just kidding...


8) There is no need to change any DC grounding (or shore power AC grounding, galvanic isolators, etc.), when installing an HF antenna and RF ground system / counterpoise.....
So, no worries there...




Anything else we can help with...let us know..

Fair winds..

John
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Old 24-05-2013, 14:32   #170
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

Mark,
Nick is correct here in his posting that it was known (and talked about) for a couple years now, that The KISS-SSB Ground was inferior and a waste of $$$...
Quote:
Originally Posted by colemj View Post
I'm getting the impression from the actual testing that it would be simpler and just as good to forgo the KISS, or any counterpoise, entirely.

Doesn't sound like either is a smart idea, though.
BUT....
But, the reason for all the testing (at least on my part), was to have actual real-world scientific proof that would counter the marketing hype and anecdotal reports....which it has done wonderfully....



Bottom line (as I have stated many, many times over the years), anything conductive can work as an antenna (and/or counterpoise) to some extent (I've made daily contacts for weeks / months straight, over paths of 1000's of miles on HF radio, with just a random wire tossed out a window laying on some shrubbery....and many more with just a wire sticking out the back of the radio, strung up with a string/rope....no "ground" no "counterpoise"...but that doesn't mean that is what I should have done!!!
It's just a question of degree (i.e. how well), and at what cost (time, effort and money)....


Just my final thoughts for today....


Fair winds...

John
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Old 24-05-2013, 14:54   #171
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

I've installed and tested on-the-air a bunch of KISS-SSB systems. They all work, right out of the box, and are extremely easy to install. Ten minutes maximum. They're well built and resistant to the ravages of the marine environment. I've got very good signal reports on both the marine bands and the ham bands from EVERY installation.

HOWEVER, as I said to Rick at the completion of his testing (on the new KISS I loaned to him), I'm certainly not saying that this is the only way to go, or that it's the best way to go. It's just one simple way which makes sense for some boats.

Over the years I have installed and written about many different types of RF ground systems on boats, including some pretty eclectic lashups. And, I've used radials on boats and ashore for some 40 years. There are LOTS of different ways to go; the KISS is just one of them and, for some boats, it makes sense as a starter system.

One thing I'd caution re: Rick's tests: some of the unstated assumptions are questionable. For example...

(1) the notion that radials are best if they're "resonant" is faulty. Radials work perfectly well whether or not they're "resonant". Resonant 1/4-wave radials just make it a bit easier for the tuners to find a match.

(2) the notion that radiation from a radial system is a bad thing. In fact, radials are intended to be high-current devices, collecting and returning un-radiated RF current to the antenna feed point (the tuner in this case), where it can be re-radiated. In artificial ground systems such as the MFJ-931, the objective is to tune for maximum ground current.

And, as we all know from basic electrical theory, ANY current thru a conductor creates an electro-magnetic field (radiation) around the conductor. The more current, the stronger the electro-magnetic field.

Radials have their place. Many tests over the years have shown that elevated radials are more effective than radials on the ground or buried. They do not have to be "coupled" to the ground.

So, too, does DC grounding have its place, particularly in bleeding off static electricity and in helping to reduce noise in the receiver. That's why Gordon West's tests showed the benefit of connecting the tuner ground to the nearest bronze thru-hull. Larger ground plates were not required.

Modern tuners such as the SG230 and the AT-140 will tune a wet noodle. But, as we all know, a dummy load tunes well but with minimum or no radiation. The objective is to create an antenna/ground system which will actually radiate as much of the output power from the transmitter as possible. And, will radiate that power in desired directions, both horizontal and vertical.

No, it's not a black art. It's a blend of both science and art. Problem is, the science is evolving -- not definitive in some cases -- and the art, too, is evolving. We know about some things which work and work well. We're not always sure why that is. Otherwise, why would graduate electronics and radio engineers spend their whole careers designing new antenna systems?

Bill
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Old 24-05-2013, 15:09   #172
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

Quote:
Originally Posted by ka4wja View Post
So, while some may wonder what all the fuss is about, spending all this time testing, etc....
In my mind, the fuss was:
a) simply to prove the lack of significant resonances of the KISS-SSB ground...
and...
b) simply to show how you could build your own "random-wire" radial counterpoise for FREE, in a couple minutes time...and have it work better than the $150 KISS...
and....
c) Lastly, I did my own on-air tests last year, and while I didn't post all the wonderful detail that Rick did, my results found my use of the sea water as my counterpoise (direct copper strap to underwater metal / Dynaplate) to be far superior.....(but these anecdotal results aren't too convincing to others sometimes, hence the analyzer tests/traces...)



John
Thank you for this John...I'm amazed when the self appointed "experts", who of course are never wrong, trounce on me when I state the simplicity of my system. Low end Yaesu, MFJ tuner, Separate random wire from the back stay and using the inside conductor of coax to attach to the tuner. I'm a low end guy and the boats general budget has been huge for this guy, so all systems get only so much $$$. I get out just fine for what my intention is, with my rig. Other examples of my low cost/go cruising now applications are: Used radar, Old stock Furuno GPS and increasing my water capacity to 120 gallons from 75 gallons instead of a $5000 water maker. I rebuilt my diesel (being a Machinist) for under $3K instead of a $12K new one.
I like to stay out of these controversies but feel me sharing my cost experience helps the newbie/low budget cruiser...Thanx again...CS
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Old 24-05-2013, 17:12   #173
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

If you quantify the worst case loss for any antenna installed over the dessert and the same antenna installed over seawater the loss is rarely more than 6db. Its then hardly a surprise that users report "oh it works great"

Who can measure 6db accurately on a cruising boat? Then again who has an accurate S-meter that can measure signal differences on SSB modulation with 30% duty cycle and with 20 to 30db of fading. Some incredible test equipment that some people install on yachts!

The could be construed to be an over simplification when you consider the overall antenna efficiency equation. However the overall point is relevant, what is the efficiency impact on a short antenna of 1 ground system versus the other? How many ohms ground loss are we dealing with?

Radiation is a bad thing from radials when it produces unnecessary high angle radiation. The only way you can counter this high angle radiation is by adding lots of long radials. Impractical on a cruising yacht. The other way to cancel this high angle radiation and too avoid noise pickup from radials is to use lots of short ones. An ideal solution for yachts.

Regardless of the ground system used, even when what would be considered a "perfect" ground would have issues of one kind or another when installed on the typical cruising yacht. We are are not dealing with 120 radials evenly spread around the yacht. We dealing with bits of wire or foil installed in a haphazard manner with no consideration of where the highest RF current density is and hence where the highest loss is.

I find it amusing that there is so much debate about ground systems when so much more could be gained by optimizing the antenna system dynamics such as loss and takeoff angle. Everyone speaks as if their antenna systems are perfect on all frequencies and have uniform characteristics on all frequencies.

Nobody here or on any other forum has quantified ground loss over seawater, so saying that any ground is better than any other is just pure speculation. It is even more irrelevant when you cant show its impact on antenna efficiency. Especially we have no impedance versus frequency data that allows us to calculate efficiency. If I was a non technical sailor I simply want to know if I use a KISS versus a piece of wire how many ohms I gained by reducing loss and improving efficiency. Or even simpler than this, what is better or what is worst. Nobody here has said what is better or what is worst because they cant prove it. Its just mere speculation based on heresay and subjective opinions.

Providing the answers is very easy to do, why is everyone skirting around the issues with endless pages of discussions when we can can calculate and give the answer in 2 sentences? Sorry I am not a ground cult member, but I get tired of these debates that never end when the answers are so simple in my mind and in the minds of engineers.

Since many are intent on proving that KISS is not efficient(which any technical person would know is right, nor works as claimed) how would you really know if you cant quantify the ground loss? Are we just going to make guestimations that an IDEAL ground system is better than the worst ground such as KISS over seawater? What is the ground loss and the field strength gain of the best ground system versus the KISS. Nobody here has really answered these questions. All we know is that a piece of wire of the same length as the KISS will work exactly the same. So the KISS goes down in history as the most expensive piece of wire in the world. The answer however is that we cant quantify the net gain or loss in signal strength of a superior RF ground installed on a yacht versus a simple piece of wire or KISS ground. This is hardly a surprise that there is so many opinions since our radios are installed above the best possible radio RF ground, its called seawater. Improving what nature has given us for free to bolster ones technical credentials or sell a product is arrogance at its best especially when nobody has told us that there is a problem and how big the problem is. What is the ground loss technical experts?

So we back to making assumptions and relying on anecdotal reports that "my ground is better than your ground system" . Pages of endless discourse that provides no quantifiable answers, much like anchor debates!

If this was the aeronautical or mobile HF forum we would have the answers in 4 posts. Since people in these forums know exactly what the problem is and have quantified the ground loss. When you dealing with installing a HF radio and antenna on a car or a plane you dealing with a limited amount of area, fixed ground loss and small antennas. We know what the efficiency of the whole system is going to be. Now we come back to sailing forums and yachts, and we go around in circles from forum too forum bashing the same subject to death with no end in site. We do this we because we cant ask simple question like what exactly is the problem, how big is the problem and how do we fix it. We just get flooded with hot air and no answers I am sorry to say. You would think that within the last decade of talking about the problems someone would have come up with a answer by now! If it was keels falling off the engineers would have had a answer in 1 month. RF Engineering is a science like mechanical engineering. I think some have forgotten this point!

The bottom line is that you trying too influence losses in an area that is about 1 wavelength around the boat. Now work out the radius of a circle at 4mhz for 1 or 2 wavelengths. Now you trying too influence loss inside this circle with small pieces of wire, foil and other bits of metal. Now as % of Sqft or Square meters how much difference is there really between 1 piece of wire versus 5, or even the best RF possible yacht ground? When you look at the problem like this you see that achieving an effective ground is an enormous obstacle when we only have a limited area to work with.

So until someone quantifies the problem in a technical manner all that most of us have contributed to this subject is a lot of opinionated hot air. If we painted in the 1st ground system in 1 color and the other second ground system in this magic circle, most ordinary people with no ground system training would say that there is little difference between 1 color as and another as a % of area. Technical radio engineers see the problem just as simply and just as clearly. When look at this problem as simply as this you can see why these ground debates on yachts are largely a waste of time because of preconceived bias and just simply a flawed understanding of what a ground system is supposed to accomplish. Hence the lack of credible measured data. Which by the way has been done in many engineering papers published by the IEEE and radio ham publications. This lack of credible imformation is one of the reason I hate getting involved in these debates because we all starting off from some preconceived notion of what we want the outcome to be and arguments not based on the facts. Very few people actually want to tell you what the ground loss figure is and how to address these losses. They dont have the answer because they dont know what the loss is, its that simple The only question we should ask is by how many Db the ground system improves your signal over any other lesser or better ground system. Nobody has answered that question in hundreds of pages of debates in here and on many other forums. So the results will always be inconclusive until someone takes a profession engineering approach and quantifies the problem. I am sure I will be seeing the same debates on forums in 5 years times because we just dealing with subjective chit chat that does not aim to answer the hard questions and provide practical solutions for sailors. We have hams intent on providing their technical prowess and others wanting to sell and promote products that makes their lives easy as installers. We have nobody that has actually defined the size of the problem(ground loss)

Adios I am in my bunker under GROUND! I might come back when someone has quantified the problem so I can pull my slide ruler out and do some problem solving! In the mean time I will stay grounded in my chair.
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Old 24-05-2013, 20:56   #174
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

I'll have what he's having...
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Old 25-05-2013, 13:26   #175
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

Oops, looks like I lost some info in my report while editing. In Test 2 I lost some of the text that explained how the test was done.

The Test 2 experiment is an attempt to demonstrate that the KISS is similar to a length of single conductor wire about the same over length of the KISS. The first column of SWR readings at various frequencies were measured with only the KISS attached to the tuner ground post and after a tune operation at each frequency. The second column are with only the wire attached to the tuner ground, but with the tune operation being done while only the KISS was attached. The assumption is that there would be a change in SWR if the counterpoise properties where different between the wire and the KISS. To validate the assumption, I included SWR readings with the existing counterpoise and with no connection to the tuner ground post.

With the system tuned while connected to the KISS this experiment shows that there is little difference in SWR readings when the KISS is replaced with the wire. The assumption that there will be a significant change in SWR when the counterpoise properties change significantly is validated by the observed change in SWR when connecting to existing counterpoise or when not connected.
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Old 27-05-2013, 02:24   #176
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

And your test results could be interpreted 2 ways. If there was significant ground loss the KISS or a piece of wire are producing no discernible difference or affect on ground loss. The other alternative explanation is that the ground loss is so low you would need a massive ground system to make any improvement over seawater. This is exactly my point in the post above. Nobody has measured or knows what the ground loss resistance is. So making claims or assertions about the effectiveness of 1 ground system or another without measured data is a very flawed way of going about solving the problem. If ground loss resistance was measured we would have a better understanding of how we would go about tackling the issue of installing a simple and effective ground system. When sailors solve the ground loss equation, then the importance of the antenna system tyoe and feed system will also have a bearing on what the bare minimum acceptable ground system is. All we have so far is endless anecdotal reports with very little science to back up claims that these ground systems can be applied or installed universally on all yachts. We will leave this to the SSB and RF Ground experts. Maybe one of these experts will provide the answers that will withstand scientific scrutiny. The KISS may well be an effective ground systems depending on the antenna system and how the antenna is fed.
Quote:
Originally Posted by svclanguage View Post
Oops, looks like I lost some info in my report while editing. In Test 2 I lost some of the text that explained how the test was done.

The Test 2 experiment is an attempt to demonstrate that the KISS is similar to a length of single conductor wire about the same over length of the KISS. The first column of SWR readings at various frequencies were measured with only the KISS attached to the tuner ground post and after a tune operation at each frequency. The second column are with only the wire attached to the tuner ground, but with the tune operation being done while only the KISS was attached. The assumption is that there would be a change in SWR if the counterpoise properties where different between the wire and the KISS. To validate the assumption, I included SWR readings with the existing counterpoise and with no connection to the tuner ground post.

With the system tuned while connected to the KISS this experiment shows that there is little difference in SWR readings when the KISS is replaced with the wire. The assumption that there will be a significant change in SWR when the counterpoise properties change significantly is validated by the observed change in SWR when connecting to existing counterpoise or when not connected.
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Old 27-05-2013, 18:08   #177
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

plebian99,

"And your test results could be interpreted 2 ways. If there was significant ground loss the KISS or a piece of wire are producing no discernible difference or affect on ground loss. The other alternative explanation is that the ground loss is so low you would need a massive ground system to make any improvement over seawater."

I assume you are referring to Test #2 and #6. In these tests there was no connection to seawater when comparing wire to KISS, other than the minimal coupling due to proximity and through the chokes on the coax and control cable on the tuner, less coupling to ground in test #6 as it was done on land. I fail to understand why ground loss is a large factor when comparing wire, KISS, can you explain? Perhaps you missed the fact that the tune operation was done with only the KISS attached, and that the wire replaced the KISS and there there was no other ground or counterpoise connected to the tuner when each SWR reading was noted for each of the 4 columns.

"The KISS may well be an effective ground systems depending on the antenna system and how the antenna is fed."

Given the typical vessel has an antenna tuner at the feed point and the antenna is long wire or whip between 16' to 60', and might operate at frequencies from 2mHz to 28mHz, please give examples where the KISS would be an effective counterpoise and why.A general response to your postings: I will argue that much of the testing I and others have reported on in this forum are scientific in that we state the objective or hypothesis, describe an experiment to test the hypothesis and report measured results. I invite you or anyone to do the same and hope that your experiment design and measurements are better than what we have done, as I readily admit that I a novice and have only rudimentary test equipment.

I suggest that with your effort on stating why you think these results are meaningless you put some effort into teaching us how we can perform the measurements you suggest are needed.

Rick
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Old 29-05-2013, 08:21   #178
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Re: The KISS SSB Counterpoise - Revealed ( with Pics )

wow... rant much?

given the thread is about the KISS, its effectivity, its cost effectiveness and then suitable options, exactly how does your practical experience on cruising sailboats help in this topic?....ah, i see you had nothing to contribute after 1000 words +/-

If you had any experience of sailboat SSB installations, you would note that there is a real limitation on antenna instals.. an insulated backstay accounts for likely 98%, followed by a whip, and a retractable spool of cable and sundry others.. So on a sailboat, the antenna is what it is... you can model this antenna till the cows come home if you wish, but it still is what it is... an insulated backstay or a whip or a piece of wire.

So, these leaves improvement in the counterpoise as the viable option for improved signal performance... and recall that the counterpoise installation is the single biggest headache in a SSB install. period...but again, after 1000 words +/- you had nothing to contribute.

I would thank everyone who has taken time and effort to discuss, explain and contribute positively to this (still) most important topic. counterpoise

Quote:
Originally Posted by plebian99 View Post
If you quantify the worst case loss for any antenna installed over the dessert and the same antenna installed over seawater the loss is rarely more than 6db. Its then hardly a surprise that users report "oh it works great"

Who can measure 6db accurately on a cruising boat? Then again who has an accurate S-meter that can measure signal differences on SSB modulation with 30% duty cycle and with 20 to 30db of fading. Some incredible test equipment that some people install on yachts!

The could be construed to be an over simplification when you consider the overall antenna efficiency equation. However the overall point is relevant, what is the efficiency impact on a short antenna of 1 ground system versus the other? How many ohms ground loss are we dealing with?

Radiation is a bad thing from radials when it produces unnecessary high angle radiation. The only way you can counter this high angle radiation is by adding lots of long radials. Impractical on a cruising yacht. The other way to cancel this high angle radiation and too avoid noise pickup from radials is to use lots of short ones. An ideal solution for yachts.

Regardless of the ground system used, even when what would be considered a "perfect" ground would have issues of one kind or another when installed on the typical cruising yacht. We are are not dealing with 120 radials evenly spread around the yacht. We dealing with bits of wire or foil installed in a haphazard manner with no consideration of where the highest RF current density is and hence where the highest loss is.

I find it amusing that there is so much debate about ground systems when so much more could be gained by optimizing the antenna system dynamics such as loss and takeoff angle. Everyone speaks as if their antenna systems are perfect on all frequencies and have uniform characteristics on all frequencies.

Nobody here or on any other forum has quantified ground loss over seawater, so saying that any ground is better than any other is just pure speculation. It is even more irrelevant when you cant show its impact on antenna efficiency. Especially we have no impedance versus frequency data that allows us to calculate efficiency. If I was a non technical sailor I simply want to know if I use a KISS versus a piece of wire how many ohms I gained by reducing loss and improving efficiency. Or even simpler than this, what is better or what is worst. Nobody here has said what is better or what is worst because they cant prove it. Its just mere speculation based on heresay and subjective opinions.

Providing the answers is very easy to do, why is everyone skirting around the issues with endless pages of discussions when we can can calculate and give the answer in 2 sentences? Sorry I am not a ground cult member, but I get tired of these debates that never end when the answers are so simple in my mind and in the minds of engineers.

Since many are intent on proving that KISS is not efficient(which any technical person would know is right, nor works as claimed) how would you really know if you cant quantify the ground loss? Are we just going to make guestimations that an IDEAL ground system is better than the worst ground such as KISS over seawater? What is the ground loss and the field strength gain of the best ground system versus the KISS. Nobody here has really answered these questions. All we know is that a piece of wire of the same length as the KISS will work exactly the same. So the KISS goes down in history as the most expensive piece of wire in the world. The answer however is that we cant quantify the net gain or loss in signal strength of a superior RF ground installed on a yacht versus a simple piece of wire or KISS ground. This is hardly a surprise that there is so many opinions since our radios are installed above the best possible radio RF ground, its called seawater. Improving what nature has given us for free to bolster ones technical credentials or sell a product is arrogance at its best especially when nobody has told us that there is a problem and how big the problem is. What is the ground loss technical experts?

So we back to making assumptions and relying on anecdotal reports that "my ground is better than your ground system" . Pages of endless discourse that provides no quantifiable answers, much like anchor debates!

If this was the aeronautical or mobile HF forum we would have the answers in 4 posts. Since people in these forums know exactly what the problem is and have quantified the ground loss. When you dealing with installing a HF radio and antenna on a car or a plane you dealing with a limited amount of area, fixed ground loss and small antennas. We know what the efficiency of the whole system is going to be. Now we come back to sailing forums and yachts, and we go around in circles from forum too forum bashing the same subject to death with no end in site. We do this we because we cant ask simple question like what exactly is the problem, how big is the problem and how do we fix it. We just get flooded with hot air and no answers I am sorry to say. You would think that within the last decade of talking about the problems someone would have come up with a answer by now! If it was keels falling off the engineers would have had a answer in 1 month. RF Engineering is a science like mechanical engineering. I think some have forgotten this point!

The bottom line is that you trying too influence losses in an area that is about 1 wavelength around the boat. Now work out the radius of a circle at 4mhz for 1 or 2 wavelengths. Now you trying too influence loss inside this circle with small pieces of wire, foil and other bits of metal. Now as % of Sqft or Square meters how much difference is there really between 1 piece of wire versus 5, or even the best RF possible yacht ground? When you look at the problem like this you see that achieving an effective ground is an enormous obstacle when we only have a limited area to work with.

So until someone quantifies the problem in a technical manner all that most of us have contributed to this subject is a lot of opinionated hot air. If we painted in the 1st ground system in 1 color and the other second ground system in this magic circle, most ordinary people with no ground system training would say that there is little difference between 1 color as and another as a % of area. Technical radio engineers see the problem just as simply and just as clearly. When look at this problem as simply as this you can see why these ground debates on yachts are largely a waste of time because of preconceived bias and just simply a flawed understanding of what a ground system is supposed to accomplish. Hence the lack of credible measured data. Which by the way has been done in many engineering papers published by the IEEE and radio ham publications. This lack of credible imformation is one of the reason I hate getting involved in these debates because we all starting off from some preconceived notion of what we want the outcome to be and arguments not based on the facts. Very few people actually want to tell you what the ground loss figure is and how to address these losses. They dont have the answer because they dont know what the loss is, its that simple The only question we should ask is by how many Db the ground system improves your signal over any other lesser or better ground system. Nobody has answered that question in hundreds of pages of debates in here and on many other forums. So the results will always be inconclusive until someone takes a profession engineering approach and quantifies the problem. I am sure I will be seeing the same debates on forums in 5 years times because we just dealing with subjective chit chat that does not aim to answer the hard questions and provide practical solutions for sailors. We have hams intent on providing their technical prowess and others wanting to sell and promote products that makes their lives easy as installers. We have nobody that has actually defined the size of the problem(ground loss)

Adios I am in my bunker under GROUND! I might come back when someone has quantified the problem so I can pull my slide ruler out and do some problem solving! In the mean time I will stay grounded in my chair.
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Old 01-06-2013, 23:31   #179
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Having beat that subject into the *ground* here's another question for the *engineers* in the crowd. My boat uses a considerable amount of 8cm wide copper foil in the ground system attached to the tuner ground. One clown told me with a straight face that RF would not travel to ground in a round wire so foil was a must. Others insist it is better but offer no reason. I understand its advantage in capacitive coupling to the seawater if run in the bilges. But other than that coupling is the advantage worth the trouble? Obviously if round wire does not make a good RF conductor we have a problem with the antenna itself ...

Any facts from science?
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Old 02-06-2013, 01:07   #180
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Originally Posted by daddle View Post
Having beat that subject into the *ground* here's another question for the *engineers* in the crowd. My boat uses a considerable amount of 8cm wide copper foil in the ground system attached to the tuner ground. One clown told me with a straight face that RF would not travel to ground in a round wire so foil was a must. Others insist it is better but offer no reason. I understand its advantage in capacitive coupling to the seawater if run in the bilges. But other than that coupling is the advantage worth the trouble? Obviously if round wire does not make a good RF conductor we have a problem with the antenna itself ...

Any facts from science?
You may be better off asking this in a circus I can't start to explain it as it took people 4 years to explain me and I never got a teachers license. But I can make a suggestion to improve your ground: make a direct coupling to the sea, for example by comnecting the foil to the grounding lug of a seacock.
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