Hello,
Need information on what others have found in adjusting a TH6DXX for best
SWR in a particular part of a band?
The TH6DXX used here is set for the CW. On 20, the SWR is as it should be.
However, on 15 and 10 meters the lowest SWR is in the phone band - on 15 it
is around 21,275 kHz and on 10 meters it is around 28,300 kHz. The TH6 is
mounted on a 125 ft tower with the guys either Phyllistran(?) or broken by
insulators every 51 feet.
It was rebuilt, including the traps, using many of the techniques discussed
on the reflector - Noalox on the aluminum joints, all stainless steel
hardware, lockwashers used under all the bolts or nuts, etc.
My present thinking is to just adjust the driven element (I can get to it on
the tower) by increasing the distance from the boom to the first trap. Then
to shorten the element's tip (outer end) to trap distance by an amount equal
to the "increase". The reasoning is by increasing the boom to first trap
distance should lower the SWR on all the bands and the reduction of the tip
to trap distance would bring 20 meters' back to its present SWR minimum spot.
Any and all thoughts are welcome.
73,
Mike, K4GMH
If the reasoning
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