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From: "Mike Dennison" <mike.dennison@ntlworld.com>
To: rsgb_lf_group@blacksheep.org
Date: Fri, 07 Jul 2006 17:49:06 +0100
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Subject: Re: LF: Antenna Tuning
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I am not convinced that this is the answer. My vertical wire is a few 
feet from my mast (admitedly a 2in pole, not a tower) and I have had 
no problems. It worked best with the pole earthed as it then looks 
like a capacitor, rather than a resistor. Worth a try, though.

Mike, G3XDV
==========

> Try to unground the tower and use it as the vertical part of your
> antenna. It could be that relatively close spacing of the coax you use
> as vertical part is coupling a lot of energy into the tower and it
> goes directly to ground and not into the ether.
>   Keep at it and best of luck.
>   de Lech, G3KAU
> 
> "J. Allen" <vy1ja@northwestel.net> wrote:
>   The tower is grounded at its base at this time, but is up on
>   insulators and 
> can be ungrounded easily by disconnecting a 1/0 grounding conductor.
> 
> The vertical portion of the antenna is a piece of coaxial cable spaced
> about 4 feet away from the tower.
> 
> Still no luck finding the first resonant point. All points have been
> checked from 20 kHz through 250 kHz. It acts like I have a big
> capacitor connected to the end of the coax. At the base of the
> antenna, I have installed a relay and can switch between the dummy
> load and the antenna base loading network. Whatever is wrong is wrong
> on the antenna side of that relay. If the dummy load is put on the
> other connector it acts as a dummy should, so the problem is not in
> the relay or its connection. If I substitute a lumped constant for the
> antenna, the traces are as expected with the scope.
> 
> I just do not seem to be able to find a resonant point using a
> frequency divider and tiny amp. The scope traces are either sine wave
> traces but with the voltage and current out of phase, or else really
> convoluted forms which are in phase.
> 
> I am still at step one. How to I get the two waveforms to coincide and
> at the same time have them look like sinewaves?
> 
> Any ideas where to go with this now?
> 
> "J" 
> 
> 
> 
> 
>