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[W8HZ]

My Cushcraft A3S recently started began giving erratic
SWR readings. I suspected the traps and so I dropped the driven element and found bugs and nesting material in the
traps. I blew foreign matreial out of the traps but when I reassembled the antenna, it performed worse than before.

Originally it was resonant at 28.5 Mhz and no other place.
Now it is resonant at 14.2 Mhz and no where else.

Any and all help most greatfully requested.

73 de Bob ...

[KF7CG]

It looks like you went from one extreme to the other while working on the traps.  Originally you had an OPEN trap; it tended to disconnect the rest of the element at the trap.

Now you have a shorted trap or possibly a disconnected capacitor in the trap and you are getting the full benefit of the antenna elements on all bands.  If the traps are truly shorted the resonant frequency should be a little high of where you tuned it.  If the capacitors are not making the correct contacts it should be low by a little