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Re: LF: Antenna Tuning

To: [email protected]
Subject: Re: LF: Antenna Tuning
From: LECH LASZKIEWICZ <[email protected]>
Date: Fri, 7 Jul 2006 15:44:27 +0100 (BST)
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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" <[email protected]> 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"




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