Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 28-02-2013, 18:24   #16
Registered User
 
ka4wja's Avatar

Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,033
Re: Ground Plane

Sorry if you misunderstood what I wrote....I'm aware of the proper use of the terms, but choose to use the terms I do, to more easily describe things (especially when teaching classes, etc...)
Quote:
Originally Posted by daddle View Post
You have it mixed up. See your ARRL handbook. Or Google counterpoise for papers on the very subject (by professionals and PhD's perhaps).
And, BTW, I've been scolded on this issue by the best of them, none other than the late L.B. Cebik....Heck he's even written an entire paper on the mis-use of the word "counterpoise".....(I assume you've read it...)

But, no worries here!!!
We all use words differently and all talk differently....and that makes life interesting!!!







I'm laughing along with ya' on this one!!!
Quote:
Originally Posted by daddle View Post
Several radio hobbyists told me that I must change my grounding conductors to copper foil "because HF currents will not go thru a wire..." Seriously? They were a bit stumped when I pointed out that the entire tuner, feed, and antenna are constructed of simple, and relatively small, plain wire. I know there can be some advantages to using foils, but in the typical case plain old wire will work well enough.
Not sure why some believe the myth...but oh well, all we can do is be non-judgmental and try to educate 'em....

And, if any one cares, I did post (on the SSCA Disc Boards) the formulas used to calculate inductance in round wire and flat copper...along with the results comparing 3" copper strap vs. 4/0000 gauge copper wire, vs. 14 gauge copper wire.....
(4/0 ga (0000 ga) wire has 11% more inductance than 3" wide copper strap... and 14ga wire has 48% more inductance than 3" wide copper strap...)
Anyone that's interested in that discussion, please have a look there, as I don't wish to clog up this thread....
SSCA Forum • View topic - A Few SSB Install Questions



Fair winds....

John
s/v Annie Laurie
__________________

__________________
ka4wja is offline   Reply With Quote
Old 01-03-2013, 05:08   #17
Registered User
 
Bill_E's Avatar

Join Date: Aug 2008
Location: New Mexico and Puerto Rico
Boat: Sunbeam, 37, Ziamar
Posts: 300
Re: Ground Plane

Well, it looks like it's time for me to start to work on my existing setup.

When we did the original install, we used the thin copper sheet available at the local marine store and laid it on the fiberglass under my starboard lazarette. We then covered it with a thin coat of West System resin. I haven't looked at it for several years, so now I'm just trying to recall details. I'll try to check it all out this afternoon so I can give more accurate details. I think we soldered the sheets together to give a large surface. So the question is: How do you make connections? Screws, bolts, clamps? I have some conductive grease that I purchased a while back.

The dynaplates are the small ones (maybe 3 x 6 inches).

Thanks for all of the comments and help.
Bill
__________________

__________________
Don't believe everything you think
Bill_E is offline   Reply With Quote
Old 01-03-2013, 05:53   #18
Registered User
 
SimonV's Avatar

Join Date: Aug 2007
Location: Brisbane, Australia.
Posts: 1,316
Re: Ground Plane

I Just installed the KISS SSB, and can not fault it. Lots of folk have told me why it should not work but none can explain why it does.
__________________
Simon

https://svgoodonya.blogspot.com.au/
SimonV is offline   Reply With Quote
Old 01-03-2013, 06:11   #19
Registered User

Join Date: Sep 2008
Location: Camden, ME
Boat: A Thistle and a Hallberg-Rassy 36
Posts: 661
Quote:
Originally Posted by SimonV View Post
I Just installed the KISS SSB, and can not fault it. Lots of folk have told me why it should not work but none can explain why it does.
Did you compare it to a simple 14 ft wire in its place? Lots of discussion on this forum and another that would answer your statement.
__________________
SoonerSailor is offline   Reply With Quote
Old 01-03-2013, 07:10   #20
Registered User
 
SimonV's Avatar

Join Date: Aug 2007
Location: Brisbane, Australia.
Posts: 1,316
Re: Ground Plane

Quote:
Originally Posted by SoonerSailor View Post
Did you compare it to a simple 14 ft wire in its place? Lots of discussion on this forum and another that would answer your statement.
Nope, its white mans magic, and I have no idea how it works, only it does. If you read all the information re the tests from others in this and other forums, there is this big question mark; but it works. At the end of the day that is all that matters, or am I missing something?
__________________
Simon

https://svgoodonya.blogspot.com.au/
SimonV is offline   Reply With Quote
Old 01-03-2013, 10:27   #21
Registered User

Join Date: Sep 2008
Location: Camden, ME
Boat: A Thistle and a Hallberg-Rassy 36
Posts: 661
Re: Ground Plane

I don't remember anyone saying the KISS doesn't work. I haven't heard anyone puzzle over why it does work. "It works" is not a quantitative concept, however.

There are some that persist in setting up a straw man (who says it can't work) so they can knock him down and claim that this device defies conventional RF theory and is something special.

Its pretty clear why it works - it provides something of a link to an RF ground that an ATU unit can use to give an impedance match to the transmitter, and its associated ground losses are low enough that typically a useable enough amount of RF is actually radiated from the antenna to make a desired contact. As proposed many times, functionally it appears to be a 14 ft fat wire (not "tuned radials"), well sealed, that could also be equaled performance-wise with a similar length of 14ga wire installed in a similar position and at a fraction of the cost. Several pieces of 14ga wire of perhaps differing lengths and differing positions in the bilge would probably exceed the performance of the KISS. Measurably? Who knows. It is so difficult to implement a reproducible test on a boat comparing differing ground schemes that almost nothing can be credibly proved or disproved. That leaves lots of wiggle room for differing schemes that are not so efficient alongside those that are, which means a marketing effort usually wins.


Chip
__________________
SoonerSailor is offline   Reply With Quote
Old 01-03-2013, 17:50   #22
Registered User

Join Date: Oct 2009
Posts: 51
Re: Ground Plane

It works for the following reasons.

1. You operating your antenna over seawater which is the best possible(lowest loss)
environment that you can operate a HF radio from. So even if you had no RF ground you would still get out and be heard. If god chose a place to operate his HF radio station from, it would be over seawater.

2. Your antenna despite the poor (KISS) ground creates its own ground from the capacitance from the antenna to the seawater. Your KISS is just marginally
helping from what is already occurring free of charge.

3. You already have a ground installed and you dont even know it even without the KISS! The coax from your antenna tuner(the shield) acts like a RF ground when you have none or a poor ground like the KISS. This coax shield is then DC ground onto all your boats bonded negative DC wiring. This connection is done in your radio. Use your multimeter and you will measure and find that your DC ground and RF ground are at the same potential(ground). Your rigging which should also be bonded for lightning protection is probably also bonded somewhere to your DC electrical system. You also have have a dynaplate installed that you did not even know about (if dont have one) Your prop shaft, electrodes and engine bonding to the negative of your battery creates another grounding path.

4. Your boat is creating a hole in the water. If you understand how RF current and radio waves work. You will understand that the RF current follows the profile of the hole in the water that the boat creates. The RF current travels in the skin depth of the seawater. What this means is that all the above RF current leakage and connections points will always connect to the seawater without needing assistance. RF current in the bilge will travel along the boundaries of the seawater hole creating a bond with seawater hence creating a RF ground.

So you see even though you thought that you were not RF grounded, you were grounded without even trying. This is the main reason why people get the illusion that the KISS works. The truth is that the KISS is barely pulling its ground weight because all the other factors and connection paths mentioned above is doing most of the pulling. Pull out all the above ground paths and you will be very unhappy with the KISS. Take your radio to the dessert and connect it to the antenna tuner in the clear and then attach the KISS to the antenna tuner. You wont be so impressed with the KISS The KISS is like one dog in a sled being pulled by 10 other dogs. It cant claim that it is doing all the work when what is already on your boat is doing 99% of the RF grounding pulling work.

If I took a piece of wire that is the same length as the KISS and connected it in place of the KISS ground your HF performance would be exactly the same! The KISS cant operate electrically as described. This is an impossibility. Its a short bit of wire that operates like a radial and because of the above environmental factors that are part of the installation gives you the impression that its a great success.

Thats why it works, its very simple reasons why it works. You dont need to the Wizard of OZ to understand why it works.

Quote:
Originally Posted by SimonV View Post
I Just installed the KISS SSB, and can not fault it. Lots of folk have told me why it should not work but none can explain why it does.
__________________
plebian99 is offline   Reply With Quote
Old 02-03-2013, 13:41   #23
Registered User
 
ka4wja's Avatar

Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,033
Re: Ground Plane

Thank you plebian....


I agree with #1 and #2...but #3 and #4 are (in my opinion) somewhat flawed... (not wrong, just flawed...)




#3 doesn't apply to most boats...
Quote:
Originally Posted by plebian99 View Post
3. You already have a ground installed and you dont even know it even without the KISS! The coax from your antenna tuner(the shield) acts like a RF ground when you have none or a poor ground like the KISS. This coax shield is then DC ground onto all your boats bonded negative DC wiring. This connection is done in your radio. Use your multimeter and you will measure and find that your DC ground and RF ground are at the same potential(ground). Your rigging which should also be bonded for lightning protection is probably also bonded somewhere to your DC electrical system. You also have have a dynaplate installed that you did not even know about (if dont have one) Your prop shaft, electrodes and engine bonding to the negative of your battery creates another grounding path.
Unfortunately this doesn't apply to most boats....at least not those that have "followed the rules"..
Most HF radio installations on cruising boats these days use a "line isolator" and/or a ferrite bead "balun/unun" on the coax, as it exits the remote auto-tuner/coupler....AND also use plenty of ferrites on the remote tuner/coupler power and control wires.....
Most retailers / installers of Maritime HF communications gear (even the big commercial guys) provide/install line isolators and ferrites....and many (all??) of those retailers/installers catering to the pleasure boat / cruising community specifically recommend doing so, and specifically sell "RFI kits" for those who have troubles and haven't done it correctly the first time...

And further since the radio DC power wires are directly connected to the batteries, it's doubtful there is much of an "RF connection" with the main house bank's capacitance involved (heck, I've even got some big ferrites on my DC power wires, right near the radio...)

(Although I've seen "line isolators" / ferrite chokes used sporadically for many years, this became SOP over the past 10 - 15 years as the proliferation of microprocessor-controlled HF radios brought some issues with RFI, and became especially recommended after the introduction of PACTOR modems, Sailmail, and with computers connected to the radios, etc....and is directly recommended by Jim Corerman and Sailmail....)









#4 is true, but if you've installed your system per the usual recommendations ("line isolator", ferrites, etc.), then you should have something attached to the ground lug of the remote tuner/coupler to provide an easier path for the RF....Yes???
Quote:
Originally Posted by plebian99 View Post
4. Your boat is creating a hole in the water. If you understand how RF current and radio waves work. You will understand that the RF current follows the profile of the hole in the water that the boat creates. The RF current travels in the skin depth of the seawater. What this means is that all the above RF current leakage and connections points will always connect to the seawater without needing assistance. RF current in the bilge will travel along the boundaries of the seawater hole creating a bond with seawater hence creating a RF ground.






Here we have some data that will be of help...
Have a look here at these tests and you'll see some interesting things...
SSCA Forum • View topic - KISS-SSB Counterpoise
Quote:
Originally Posted by plebian99 View Post
If I took a piece of wire that is the same length as the KISS and connected it in place of the KISS ground your HF performance would be exactly the same! The KISS cant operate electrically as described. This is an impossibility. Its a short bit of wire that operates like a radial and because of the above environmental factors that are part of the installation gives you the impression that its a great success.
a) The first FACT is that nobody is going to be able to design/build a 14' long "radial" that is stuffed with hundreds of feet of wire, and actually have it "resonant of all ham/marine HF freqs"....it is, for all practical purposes, IMPOSSIBLE....
So, once everyone accepts this as fact, you can move on.....and if you care to see what very few resonances (none really) it actually has, the test results are all public for you to see on the link above....
b) Another FACT is that whatever piece of wire (or the KISS) you connect to the ground lug of your tuner and place in your lazarette / bilge IS going to be "de-tuned" by both its close proximity to the sea water and all of the other electrical conductors around (whether wires, ss tubing, metal tanks, rudder posts, lead keels, engines, shafts, struts, etc...)
Here again, the tests results are public, have a look at the above link if you desire....
c) To give the KISS a fair shake, it does have a couple minor resonances (semi-resonances), but as can easily be seen from the tests a couple random lengths of copper wire (yanked out of a dumpster for free) actually provides better resonant radials.....and if you spend a few minutes to trim 'em, you can make your own quasi-resonant radial system for < $5 worth of copper wire, that will perform as well or better than the KISS....





Sorry if I'm adding too much complication to an easy answer....I just wanted to point out that there ARE fairly easy answers, but sometimes it takes a bit more than a couple of sentences to convince....


On a side note, I wonder where/who these guys are that "constantly say this or that doesn't work".....'cause if you read the SSCA disc boards or even here at CF, you usually get the straight scoop.....
Oh well, I haven't been to other sailing boards in quite a few years...so maybe I'm missing something....



Fair winds...

John
s/v Annie Laurie
__________________
ka4wja is offline   Reply With Quote
Old 04-03-2013, 02:14   #24
Registered User

Join Date: Oct 2009
Posts: 51
Re: Ground Plane

Hi John Well we will just have to disagree. I think I would be safe saying that 99.99% of yachts that have a HF installation do not have RF chokes installed. I think you really speaking from ham experience more than sailing installation experience. The other point is that very few people will have installed chokes with choking impedances well over 3000 ohms across the HF spectrum. I would like to see a common choke that provides 5000 ohms of choking impedance over the HF range. On point 4 you effectively telling me skin depth does not exist if the hole in the water theory is invalid. We will just disagree and leave it at that. This is not the place for such debates. Thanks for the links on the KISS ground. I am not really interested in getting involved in RF ground debates. Most yachts have adequate HF installations and any extra performance beyond this is wasted effort. I know that you serious hams will disagree. I am not interested in being a big gun DX'er on a yacht. I like most sailors do the basics weather, PACTOR, nets and some hamming. I like others get out well enough and an extra 3db to 6Db is not going to make or break any HF radio installed on a yacht.All these in depth debates are not necessary information for most sailors and serve no useful purpose except for those who are mad hams.
__________________
plebian99 is offline   Reply With Quote
Old 04-03-2013, 07:46   #25
Registered User
 
ka4wja's Avatar

Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,033
Re: Ground Plane

1) Yep, no argument here....we'll just disagree, politely and respectfully....
Quote:
Originally Posted by plebian99 View Post
Hi John Well we will just have to disagree. I think I would be safe saying that 99.99% of yachts that have a HF installation do not have RF chokes installed. I think you really speaking from ham experience more than sailing installation experience. The other point is that very few people will have installed chokes with choking impedances well over 3000 ohms across the HF spectrum. I would like to see a common choke that provides 5000 ohms of choking impedance over the HF range.
All of the marine HF radio installations I have seen (dozens++) over the past 10 years or so, and all of those who have followed Sailmail and others recommendations, and all of those done by the 3 or 4 radio installers that I know, etc....have had line isolators installed in the coax line at the remote tuner/coupler, and ferrites placed on the tuner control wires...

While one single clip-on mix 31, might have only a few hundred ohms impedance each, most line isolators have many thousands of ohms imp across the entire HF spectrum...(something like 35,000 to 75,000 ohms is the spec that Radio Works markets....and I think a similar amount from DX Eng, but I don't have my paperwork handy...)
The ones I use (and are used by most marine HF radio dealer/installers, and have been recommended by Sailmail for 10+ years) are those from Radio Works and DX Engineering....
http://www.dxengineering.com/parts/dxe-fcc050-h05-a
T-4

So, while we may disagree, I stand firmly behind my position that if marine HF radio installs are done correctly, they will have little RF grounding other than that attached to their remote tuner/coupler's grd lug....







2) Here do agree....just my poor description of what I mean...
Quote:
Originally Posted by plebian99 View Post
On point 4 you effectively telling me skin depth does not exist if the hole in the water theory is invalid. We will just disagree and leave it at that.
Actually we agree on the skin depth issue, perhaps I wasn't very clear...sorry about that
Yes, the sea water does provide a fairly good ground path, as we agreed on in point #2....

I was just saying that I believe (my opinion) there is better coupling to the sea water if there is something attached to the grd lug of the tuner, rather than leaving it up to whatever capacitance there is between the grd lug to whatever may be in the bilges and the sea water....
Being that the RF is effectively blocked from flowing along the outside of the coax, control wires, etc. in most installations (see my comments above), having something attached to the ground lug will help....again, in my opinion...
As you said: "What this means is that all the above RF current leakage and connections points will always connect to the seawater without needing assistance. RF current in the bilge will travel along the boundaries of the seawater hole creating a bond with seawater hence creating a RF ground."
It's just that if the RF is blocked by decent line isolators and ferrites (as is the case in most marine HF installations done in the past 10 years), having something attached to the grd lug is a good idea...




Again, no argument here....we'll simply politely disagree....
Especially on your last point....as I don't think I'm mad at all....maybe a bit "kooky" but not a "mad ham"....


Fair winds...

John
s/v Annie Laurie
__________________

__________________
ka4wja is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 13:34.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.