At 09:30 AM 2/14/2012, Tom Martin wrote:
> Excessive RF took out the front end of the FT-1000MP after 2 hours.
> Lost 10 meters on the PRO II on
> Sunday. As of Monday morning, no receive or transmit with the PRO
> II on any band.
When I first tried SO2R I was concerned about high RF levels from the
tx antenna coming back down the rx stn line and zapping the receiver
on the other band(s), so I rigged up a simple RF voltmeter and
actually measured voltages presented to the rx.
A combination of stubs and filters got it down to <50mV on most
bands, a max of 200 mv on only one.
This worked for me with pairs of IC756, 756P3, Elecraft K3, and now
Flexes - I have never had any front end damage from SO2R at 1KW from
Quadras. My antenna separation is typically 100 ft or so.
What is the most I can tolerate? I don't know, but I assume it would
take more than a half volt to punch through the typical SS devices in
the rx front end.
Jerry W4UK
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