[Top] [All Lists]

[CQ-Contest] CW Filters & When to use them

Subject: [CQ-Contest] CW Filters & When to use them
From: Ken.Silverman@zool.AirTouch.COM (Ken.Silverman@zool.AirTouch.COM)
Date: Thu Sep 18 18:06:44 1997
Ken Silverman@AIRTOUCH
09/18/97 05:06 PM

While I haven't read all the mail on this one, I thought I'd throw in some
other considerations on filter selection.

One of the key things I am concerned about is the insertion loss of the
tighter filters.  Normally I like 500 Hz cascaded filters, and will never
use 250hz filters in contests (especially from the DX side, from which I do
a lot of contesting).

But there are many times in order to hear the weak ones, I need to use the
2.1/2.4 khz SSB filters.  That 1 or 2 dB of extra insertion loss can mean
all the difference in hearing the signals.   In the past year or two, the
15m band openings from N6RO into Japan on 15m have been veeery weak, and
the only way I can hear the JA stations is with the SSB filters.  If you
listen on the 500hz filters you hear NOTHING.  Open the filters up and
there are lots of really weak stations calling, but they ARE workable.  The
disadvantage to the wider filters is that I get pounded by adjacent
stations... but I would rather take the in-pass-band QRM and make QSOs,
than not to make the QSO at all.

Like I said earlier, I don't use the 250hz filters.  But I would also
assume that the extra insertion loss of the 250hz filters over 500hz
filters would have the same impact - that is - not hearing the weak ones
who call.

Kenny K2KW

CQ-Contest on WWW:        http://www.contesting.com/_cq-contest/
Administrative requests:  cq-contest-REQUEST@contesting.com

<Prev in Thread] Current Thread [Next in Thread>