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Old November 10th 04, 01:17 AM
sideband
 
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Dave:

Of course I understand that reasoning. I don't think the function of
the star was to act as ground radials at all, but to increase the
coupling to RF ground. I had a mag mount Wilson 1000 on the roof of
the cab of a '94 Ranger pickup. It did well. I added the star, it did
much better.

Forgive me if I'm rambling a bit. I just got back from surgery and am
flying a bit high on Vicodin. Just had my gallbladder out this
morning. They used a scope to do it. Pretty cool. I have pictures.

-SSB

Dave Hall wrote:
On Mon, 08 Nov 2004 20:24:56 GMT, sideband wrote:


Dave:

I noted increased signal strength with it on, on both transmit and
receive..

The star didn't touch the "active" side at all.. it was on the shield
side of the equation..

Perhaps the star, being so close to the sheetmetal of the roof (on the
magmount), increased the capacitance, thus increasing the capacitive
grounding, providing a better RF ground. Who knows. I didn't have the
equipment to test for that 10 years ago when I had one I don't now,
either.. All I know is, it did more than look cool.




But you do understand how it would be difficult to understand how a
series of small radials could do a better job at being a counterpoise
than the large amount of metal in the car body? A good counterpoise is
all about surface area. For a counterpose to be effective at CB
frequencies, the radial length has to be at least a 1/8th wave which
is about 4.5 feet.

The numbers just don't add up. But this isn't the first time I've
heard people swear that some "product" they bought improved their
performance, and it made no logical sense from an engineering
standpoint, so who knows......

Dave
"Sandbagger"