Hello,
because I am not a real HF-/NF-/Filter-expert, like Ekki/DF4OR and others
here, I have enjoyed to learn more about the pro and contra of 250Hz filters
in the RTTY mode. So much about the theory ...
But what's about the practice? When - in which situation - you are using
which type of filter and/or which filter-combination in a RTTY-contest
and why?
In a RTTY-contest I am using the 500/500Hz-combination; especial when
I am CQ-ing. I want to hear, if a strong neighbour comes up (suddenly) and
also I want to hear the stations (easier), who are calling me real off-freq.
When I am searching for new stations (S&P), I am switching to the
250/250Hz combination (in the first IF and second IF stages), to find
the weak ones also, who are CQ-ing very close to a very strong station or
are "sitting" between two strong stations. With the 500/500Hz-combination
I have made the experience, that I don't find them in allmost all cases.
Before you are asking; yes I have the AGC in "FAST" mode. :-)
Let us think about the many (new?) RTTY'er, who are tuning of the bands
in a contest and handing out some points; just for fun. Do you believe,
that they are using filters (250..500Hz) allways? Do they have a filter
in the first IF? Do they have switched their AGC to "FAST" allways?
When you know, that you are producing a big signal usually, maybe you
don't care about the answeres to my questions, because you will be heard
by "everyone". But when you are CQ-ing and producing a week signal, more
or less allways, like me; then you will take care about the answeres to
the questions above; believe me. :-)
73 de Waldemar, DK3VN
--
GDXF#207:Big antennas, high in the sky, are better than small ones, low!
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