Hi Mike: I was thionking like W7WHY's email response; that you will have
to adjust all of the hi-vswr elements, (reflector/directors)including the
driven element to affect any change in vswr. Thats easier said than done..
But you could 'try' the driver first and see what it does. If no
improvement..then you are gonna' have to crawl out on the boom to get to
the others!! (Sure!)
Better yet would be to tilt the antenna...unless you are part monkey!
Mike K5UO
At 08:55 AM 12/29/98 -0500, you wrote:
>
>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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>
>
>
bragassa@glasnet.ru
bragassa@hal-pc.org
k5uo@dxer.net
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