Dave Wright wrote:
>slightly high SWR on 10, 1:8:1. On 15/17 it was fine @ 1:2:1. 12 & 20
>meters are virtually flat @ 1:1:1. (using 4 meters
>rig/tuner/amp/mfj-249 and averaging.)
>
>Now it's slowly climbing on 10- it's over 2:5:1 which precludes my >usage of
>the amp. 15 & 17 now seem to be following- From 1:2:1 up to >1:8:1 now. The
>factory told me to check the length of the coax/shield >"Y" at the feedpoint
>and try making it shorter.
Hi Dave !
When you mention using the 4 meters, where are you measuring
the SWR ? At the yagi feedpoint or in the shack at the end of
the coax ?
Right NOW, the 2.5:1 SWR on 10m ... is that measured in the shack
or at the feedpoint ? If that's in the shack. I'd climb (safely)
the tower and make a jumper to hook up the MFJ unit directly to
the feedpoint and see what the SWR shows there. If it's low at
the feedpoint using the MFJ unit, then I'd suspect the coax
has become contaminated due to moisture or ???
Let us know back what you discover as the problem ...
73 and HNY !
Bill AA4NU aa4nu@ix.netcom.com
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