Topband: Inverted L SWR change

[Gary Smith]

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