Actually, given the number of emails we have seen
recently about flags, pennants, loops and other
negative gain receive antennas, it is surprising
that anybody would question using a sensitive
receiver on 160 meters. As W8JI points out, you
can always put an attenuator inline with an
overly-sensitive receiver, but there is nothing
outboard that can be done to fix a poor IMD issue.
Given the RX antennas I'm going to be using, I'm
actually going to have to add preamplifiers to
them!
high level input mixers to sustain such a
signals. Pair of power MOSFET would
do but they are not commercially offered as a
mixer...
Actually, you'd rather use a quartet of MOSFETS.
There are some in the Motorola MRF line that are,
I believe 30W RF power output capable with noise
figure of 7 - 8 dB. I always thought they'd make
nice mixers, but other projects prevailed.
I always thought my IC-735 was a nice (but not
great) radio until I started trying to listen to
DX on 80 and 160. It was nearly useless.
Switched to using a Drake R-4B and suddenly I
could hear. The problem was PLL phase noise in
the Icom. Not fixable with external anythings.
Dave W8NF
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