Hi John: The filter in any good radio will have a shape factor of about 2:1 using the 6 dB and 60 dB points. (They're pretty much industry standards.)
Guesstimating the 30 dB points, I'd say a 2.7 kHz filter would land around 4 for the 30 dB points. A lot of curves are available at http://www.qth.com/inrad/ and then following the instructions if you want to see some real life curves. Chuck -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John H. Bryant Sent: Friday, October 13, 2006 9:00 PM To: [EMAIL PROTECTED]; Mailing list for the International Radio Club of America Subject: Re: [IRCA] Winradio G313-E <CLIP> Where your main DXing filter may be 2.7 kHz wide at 3 dB down, it may be 15 or more wide at 30 dB down. The result of that is that you use narrower filters that you really want to, to conquer adjacent channel QRM <CLIP> JHB _______________________________________________ IRCA mailing list [EMAIL PROTECTED] http://arizona.hard-core-dx.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [EMAIL PROTECTED] _______________________________________________ IRCA mailing list [EMAIL PROTECTED] http://arizona.hard-core-dx.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [EMAIL PROTECTED]
