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Preamp de-sensing



I am just getting back into the satellite side of the hobby and recently put
back up my antennas and pre-amps.  Radio is the Icom 910.  Using the KLM
circular antennas (CP14 and CP30) on a fiber glass cross boom. One is mounted
with the elements vertical/horizontal and the other is turned 45 degrees.  TO
complete the system I am using SSB Electronics pre amps (SP-2000/SP-7000)
mounted on the roof tower.

The problem is that I am getting a tremendous amount of "de-sense" and "hash"
when either pre amp is turned on and I am transmitting on the other antenna.
Problem is worst when transmitting on 144.  ON SSB the S meter goes up to S9
on the 910 and I can here "hash" as I talk.   When using FM and the power all
the way back to minimun (supposely 5 watts), the S meter shows S3 and at full
power on 144, it shows about 40 over S9..

The problem is not near as bad when transmitting on 435.   No interference at
5 watts and only about S3 at full power.

I was on the satellites several years ago with a very similiar setup, except
was using a FT736  and the larger KLM antennas;  but the same pre amps.  I
don't remember having this kind of a problem then, but that was over 5 yrs ago
and before I turned old and senile

Is anybody else using a similiar setup and have the same problem; or better
yet, solutions.

Thanks

Dick K8ZTT
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