I use 250, with an Inrad filter, all the time for RTTY. Any wider than that
is too wide for me. Not sure about narrower as I can't get less than 250
cycles here. The number 2 radio here has a 500 cycle filter and that is WAY
too wide. for contesting. 73
Tom W7WHY
Don, AA5AU, wrote:
> I think I remember someone, maybe Chen, saying a 200 Hz
> filter would not work on RTTY or something to that effect.
> Maybe I don't have the story just right, but it appears to be
> working great. Too tight for contesting, but works when required.
A passband narrower than about 280 Hz removes some of a 45 baud signal.
OTOH, I have used a 200 Hz DSP filter a lot in contests and pileups because
removing off-frequency signals is a bigger benefit than the little bit lost
with the too-narrow filter. This requires precise tuning but helps separate
signals. Even 150 Hz works pretty good, though I never go that narrow.
73,
Ed
--------------
Ed Muns - W0YK
www.w0yk.com
_______________________________________________
RTTY mailing list
RTTY@contesting.com
http://lists.contesting.com/mailman/listinfo/rtty
_______________________________________________
RTTY mailing list
RTTY@contesting.com
http://lists.contesting.com/mailman/listinfo/rtty
|