The L is about 158' long with 40+ 130' radials. To match it I neded
to parallel a 90PF and a 200pF doorknob. It resonated at 1820. I was
away for Christmas and got back today and used the auto tuner in the
K3 and saw it took longer to tune than usual and instead of 1.1-1 as
usual it was 4.6-1
I used the MFJ-429B and verified instead of resonance at 1.820 it was
resonant at 2.560
The same radial plate/radials are used on 80M and with a butternut
HF9V. Checking them, all seems fine as before.
Donning headlamp and tools I went to the base of the L and all
appeared intact. I took a reading at the base of the antenna and
indeed resonance was around 2.560. I could see nothing awry. Looking
at the end of the L, all seems well and nothing apppears broken
I checked the connections and all were intact. Thinking it might be a
bad doorknob I replaced them with two 500pF seriesed doorknobs and
around 2.700 it was a perfect 1-1. I played around with different pF
ranges and was unable to get any sembalance of resonance in the 160M
area. buffing all connections made no change.
Finally I bypassed the capacitors entirely and found resonance was
around 2.170 but the SWR was 1.4 at best. The K3 autotuner matches it
1.6-1 and the 425 seems to be OK with it but I can't understand what
would have caused this change.
A the best resonance appears higher than 1.820 It almost seems like
the best thing for me to do would be to add some coil instead of
adding capacatence. I just can't imagine what would have caused this
to happen.
The only thing I can conjure is somehow the wire separated and the
intact insulation is making it look complete but instead of a full
length of wire, it's a shorter length with a gap between. There are
no sharp bends anywhere nor kinks for such an occurrence to happen so
I really doubt that is the answer. I suspect the truth lies
elsewhere.
Ideas at this point?
Gary
KA1J
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