Bill and Frank, dudes, chill, I think I hear that winter stress creeping
into your 'tude. Yes, your hear clipping and yes its overloading your mixer,
and yes the circuit is based on solid rf design. This may be a weak point
for having the benefit of having general coverage below 1.8Mhz, but it's
what makes the reciever so nice on the ham bands. The fact is that the RF
energy in excess of what that first mixer can tolerate is getting into the
radio from AM broadcast. It's always going to hamper the radio when you have
that spike (of rf) in db getting past the lpf stage. If the spike is there,
the radio is capable of removing say 45db of that energy, but when the
energy exceeds that and combines with other strong AM rf energy the first
stage of the reciever is blotto. If you observe this on a communications
monitor, you get an idea of the proportion of energy that the front end is
trying unsuccessfully to filter. You might say at this point, why doesnt
this happen on other radios? Answer is, get over it. For what you do have in
available RF design, the front end is a modern miracle. The glitch is, as a
ham, why do I have to deal with it when no other radio does this? The answer
is you dont have to deal with it. By using a high pass filter, also known as
a Broadcast Band filter, attatched to the radio, the problem is solved.
The software/firmware in the radio has nothing to do with this issue.
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