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Re: Mode VS with 2mtr IF


On the subject of de-sense of the 2mtr IF....
I run a mast mounted transverter for 23cms portable operation. This is an
old Microwave Modules box, recrystaled so that my IF is at 145.200 This
comes down to an FT290 mk1 on RG58. 10ft away is the 2mtr talkback antenna ,
driven with 100watts of SSB at around 144.175 On this system I see absolutly
no signs of desense. We do get SOME desense on the 13cms system, but that is
running an IF that is 25kHz away!
If I do not get problems, I would think that an AO51 S band IF od 145.200
and a low power (5 watts?) TX at 145.920 would be fine.
Try it, you may be suprised!

My multiband system (currently under development):
I have a 2mtr IF for the S band downlink, but this is converted to 10mtrs by
an old MMC 2mtr-10mtr receive converter (flee market cheepie) at the S band
converter. This means I can still use my 2mtr TX for V uplink or for driving
the TX converter for L band TX. I also plan to put converters in the V and U
RX lines, so all RX will come down to the shack on 10mtrs.
This takes a lot of the juggling out of mode switching.
You may need to modify the converters to avoid having excess gain though.

Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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