[RTTY] Filters

Charles Morrison cfmorris at bellsouth.net
Tue Mar 23 10:19:19 EST 2004


Date:	Tue, 23 Mar 2004 05:39:21 -0000
From:	"David Ashworth" <fathom at Access4Less.net>
To:	<RTTY at contesting.com>
Subject:	[RTTY] Inrad filters for rtty question
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Enjoyed the last contest and have a question for any operators that may be
using a Kenwood TS850.  I seem to have one Kenwood filter in my radio
(YK-88SN1).  There are two more empty slots for filters, one is for the 455
KHz IF and the other for the 8.83 MHz IF.  As the contest got going, I used
the slope tune control to neck down the signals, but perhaps another filter
would also help.  I see that Inrad makes several filters-a 250 for 455 and
8.83 and a 400 for 8.83.  Wonder which filter(s) would be a good choice to
reduce the adjacent stations but not get too narrow?  Thank you for your
help, Dave, NC6P.


Dave,

I've found that in my 850, the biggest improvement was adding the second
500hz filter to the 455 if, and using both 500 hz filters.  In my 850, I've
got the 2 original Kenwood 500hz filters, the 8.83 and the 455, and an Inrad
250 in the 8.83.

As it turns out, not to knock the 250, but going from 2.7k in both if's to
500hz in both if's was a bigger improvement in crowded bands then going from
both 500hz ifs to the 250hz in the 8.83if and the 500hz in the 455if.

As it turns out though, I don't think I've left the 455 if in the 2.7hz
setting and switched in the 250hz 8.83 filter..

I think the 455/500 is more expensive then the 8.83/250 though.. so it may
come to dollars and sense.

Charlie
KI5XP




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