I am not a good CW contest op so I can't offer my personal experiences
but I have been quite interested in CW contesting (if I can ever get up
the courage) and have asked a lot of questions pertinent to your message.
N4AA, one of the finest contest cw ops I know (next to KH5ND), has made
the statement to me that 500 Hz was just right for contesting: that a
250 filter would exclude some of the incoming sigs and was really too
For what it's worth.
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