Though to play the devil's advocate that if you do have a problem
with something generating IMD in the front end (e.g. a flaky or
poorly biased PIN diode or a connector with corrosion or whatever)
then that will generate IMD for HF signals too
But you don't seem to be noticing it right now because you don't have
an "always on" -20dBm HF signal (or whatever the UHF signal is ... I
live very close to multiple FM/TV powers in Seattle so I'm expecting
the worst).
The IMD may (will?) be there on HF too unless the cause is something
oddly resonant in the box at UHF pushing up the RF voltage (though
not the power) and cause frequency specific IMD.
That might be a motivation to fix it :-)
On Dec 13, 2007, at 10:42 AM, Dr. Gerald N. Johnson wrote:
I would just leave the filter connected to the rig and forget
about it.
It works.
Paul, W9AC
73, Jerry, K0CQ
-...-
73 DE N7WIM / G8UDP
Kevin Purcell
kevinpurcell@pobox.com
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