Dear Allan,
I did not follow your antenna problem step by step, but possibly
this may be the reason of mistuning:
The vertical part of your antenna - the coaxial cable - is too close to your
grounded tower. So the HF possibly flows through this capacity directly into
ground. How long is this vertical part? And how long are the horizontal
wires? Are you shure that there is no connection between the horizontal
wires and the grounded tower? Please disconnect the grounding. What will
happen?
Years ago I had a problem similar to yours with my FRITZEL-tower, the
vertical part - also coaxial cable - was too close to the mast. I had good
antenna current, but the stations did not hear me. After spacing the cable
for 4meters I made the first QSO´s, with lower current.
73 Walter DJ2LF
-----Ursprüngliche Nachricht-----
Von: J. Allen <[email protected]>
An: [email protected] <[email protected]>
Datum: Freitag, 7. Juli 2006 05:25
Betreff: LF: Antenna Tuning
>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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