On Sat, 3 May 1997 22:14:25 -0500 "Allan Allmand - N5CA" <n5ca@flash.net>
writes:
>Hello,
>I have recently put up a klm kt-34a. The vswr on 10 mtrs is:
>28050 - 1.6:1.....28700 - 1.8:1
>15mtrs is:
>21050 - 1.8:1.....21450 - 1.7:1
>20mtrs is:
>14002 - 3.5:1.....14350 - 3.0:1
>The ant seems to resonate at 18622 (1.1:1) with a mfj swr analyzer.
>The ant is up 50 feet on rohn 25g.
>the demensions were checked and all seemed ok.
>Has anyone had similar problems?
>
>Tnx,
>Allan
>N5CA
>
>
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>
I would guess that it's either a high resistance connection,
or an assembly error. With an swr this bad, it almost has to
be in one of the driven elements. Take a close look at the two
driven elements through binoculars to find assembly errors.
The best check of each element half is to connect an ohmmeter
between the 10 and 15 meter capacitor cans. This one measure-
ment checks EVERY connection in the entire trap assembly. If
it's over 0.5 ohm (after subtracting ohmmeter lead resistance),
it can be improved.
If there is an AM Broadcast station nearby, make sure you
verify the MFJ analyzer readings with a conventional swr
bridge.
Dave Hachadorian, K6LL
k6ll@juno.com
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