I have a TS-850 with a 1.9kHz filter in the 1st IF and a 500 Hz in the
2nd IF (both Kenwood stock). When I first installed them, I was hoping
that the 1.9 kHz whould help cut the adjacent channel interference while
letting me use the slope tuning control. I could then use the 500 Hz
filter once everything was zero beat, if I needed it.
What I have found is that using the slope tuning with the 1.9 kHz
crystal filter is *quite* different than with the 2.4 kHz stock RC
filter. I have to rotate the low cut to almost 1 o'clock to get signals
on the "other side of zero beat" suppressed. And then there are only a
few steps to the high cut filter before it is on top of the BFO
frequency. I generally don't use it.
So now during a contest what I usually do is to use the stock 2.4 kHz
with the slope tuning controls to make sure I'm near zero beat with a
station and that I've cut out most everything farther away than +/- 500
kHz. If I need to suppress stations very close in frequency to the
desired signal, I punch in the 500 Hz filter in the 2nd IF.
Someday I'm gonna hookup the microphone and see how that 1.9 kHz filter
works on SSB, which is what it was designed for!
Also, I almost never use the AGC, I run the input wide open. I was
initially fearful that this would cause all kinds of intermod, etc. But
it doesn't appear to and I don't get "caught" by nearby strong stations
tweaking the AGC.
73 de Jack, KU0KU, Kansas City
<jack.sippel@nellcorpb.com>
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