Hello all,
On the subject of narrow filters,s/n,QRN,QRM,snaging dx,and whatnot.
It has been my experience that the RF gain setting can be of a
greater use in making a cw signal rise out of the noise than the use
of dual filters.I start with the 500 HZ filter in the 1st IF and use
the RF gain setting to give me the best sounding s/n ratio possible
with this control.In some conditions I find the 250 HZ filter in the
1st IF sounds better.I usually find only when fighting QRM is
a dual filter combo needed,and then I don't get a better sounding CW
signal,but instead a little less QRM from the signals I don't want to
hear.I find that the dual 250 hz filters are great when the QRM is
almost right on top of my target signal,but I find the sound quality of
receiving is better with less filtering invovled.On a quite day,I
use the 1.8 Khz filter when just tuning around so as not to miss
signals,but with some QRN thrown into the mix a 500 Hz filter takes
out a lot of noise.In a pile up,the dual 250s really shine as they
cut the enemy down to size.But if it's just me amd joe sitting on a
clear frequency without a single QRMer in hearing range,then I just turn
off the filters and crank back the ole RF gain knob till the hiss dies
and Joe's signal shines and all is good with the world.
73,
Dean KR4IU
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