I got numerous replies to my problems with the dual driven element strap
problem on my KT-34XA.
1. The strap connections are bad. I did tighten them up to Bruce's specs
so that is a remote probabability.
2. The straps touch with motion and wind. I think this is getting
close. I looked at the strap with binoculars
and the leaves have left a residue (they all fall in November and
December in Atlanta) that motion might stir up.
I feel the material on the insulator may be the problem and it
rained last night and the SWR stopped changing and
stopped on 3 to 1. This morning its dry so its back to changing. I
plan on fully inspecting the strap and replacing the insulator.
3. K1VR and others say I need to change the coax or hardline as this is
probably the problem. I just put a new piece of 1/2 inch
hardline from the beam to the switch box. I will of course check
the connections as I have lost a pin in coax before.
4. Others point to the balun. I put a new KLM balun in and it was tested
for two months before raising the beam.
5. K4VT recommends replacing the 34XA with a Cushcraft X-9. Gary says
his X-9 performs better than his 34XA he had for
20 years. Mine is at least that old as it was originally a KT34X.
If I replace the 34XA I want 12 and 17 coverage so I can replace
the 12 meter W9PNE type X beam, too. (I use my Cushcraft 402CD on
17).
One additional point....several months ago Bruce told me that if amy of the
new caps (blue/green) split the SWR will go up quickly and then return to
normal. There was one cap on the first driven element that split on one
side and one on the 1st director both affecting 20 meters. Bruce told me
that no matter how careful (I used his technique of heating the caps before
sliding them on the elements) they will split...and the split occurs in the
first few days after installation.
Thanks for the ideas. Good luck Bruce and RIP KLM.
73 Dave K4JRB
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