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Date: Thu, 09 Nov 2006 13:53:04 +0100
To: LF-Group <rsgb_lf_group@blacksheep.org>
From: Dick Rollema <dickrollema@casema.nl>
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Subject: LF: CW-filter
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Status: O

Thanks to all  who made suggestions for the CW filter.

I know Harry Grimbergen, PA0LQ, very well. We were colleagues during our 
working lifes.  The filter I use actually is one like Harry's one but 
with  four passive tuned circuits  instead of the opamps Harry is using.  I 
am very satisfied with the filter  but it does not provide a "brick wall" 
response.  Filters as used in software defined radios do that and I was 
looking for such a filter that could be used between the output of my 
receiver and the headphones.

I will try the suggestions made by you; hopefully there is a "brick wall" 
one  among them.

73, Dick, PA0SE