Hi J,
I must agree with Mike (below) as my vertical wire is about 5 feet from the
grounded mast & I have no problems with SWR or tuning etc. May be you need
to check for a break in the vertical as Bryan suggested.
Gary - G4WGT.
-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Mike Dennison
Sent: 07 July 2006 17:49
To: [email protected]
Subject: Re: LF: Antenna Tuning
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" <[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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