20+ years ago while working the grave shift on 160 I discovered that on
SSB under noisy conditions the wide filters allowed me to copy better
than the narrow ones. Of course this was only true as long as the band
wasn't too crowded . I tried the same technique on CW and it worked.
Since then I've had similar results on RTTY. So narrow is good under QRM
but without the QRM wide can be better. I'm sure a tech head could
explain this, but that is not my strength.
73 W0ETC
On Wed, 25 Aug 2004 00:50:07 -0700 Bill Turner <dezrat1242@ispwest.com>
writes:
> On Wed, 25 Aug 2004 00:14:49 -0700, Kok Chen wrote:
>
> >I regularly copy RTTY with a cascade of two 250
> >Hz INRAD filters. Only occasionally, a 400 Hz/500 Hz cascade
> provides
> >better copy than with the 250 Hz IF filters.
>
> _________________________________________________________
>
> I have seen the same thing on occasion. A signal will be slightly
> better copy
> on my 500 Hz filter than on the 250 Hz, but only in QRM-free
> conditions, of
> course. In a contest, I use the 250 Hz filter exclusively. Any
> wider would not
> be effective. :-)
>
> --
> 73, Bill W6WRT
> QSLs via LoTW
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>
>
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