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Re: 2 meter uplink interference on 70 cm downlink


Thank you all for answering on my question. I have now a pretty good idea of
the problem.

Herewith I will answer Tony's questions:

Tony wrote:
 >We might need a bit more information..
 >Does the interference occur all the time, or only while you're

The interference occures only whil I am transmitting.

 >How well can you hear other stations on the bird?

I can hear other stations quite good. When I am transmitting it is a lot

 >What does the interference sound like?

Difficult to describe, since I have also LF detection of my SSB signal in my
headphone (the Donald Duck voice). At the other hand I see the S-meter of
the 70cm set moving to S4 (the downlink signla is only S2) when I am

 >All these may need to be answered to determine the cause, and hence the
 >solution to your problem.

By the way I am using:

FT 290 R, 2 meter all mode with amplifier (25Watt) , into a J - pole antenna

FT 780 R  with a 10 loop helix antenna and a SSB Maxi amp pre-amplifier at
the antenna.

When I am using mode A on RS12/13 I don't have any problems (except somtimes
LF detection on my headphone).



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