Hi Dennis, I have a possible selectivity improvement mod planned for the DT-400W receiver when I get the time. I have purchased some small, 4 kHz @ -6 dB filters (450 kHz I.F.) that show promise when cascaded in series. I have some specific values of capacitors, too, that are necessary between the filters to avoid degrading the total shape factor. The two filters together are a small enough assembly that they will fit inside the radio easily, similar to the selectivity mod I made to a DT-200VX (which Richard Allen now owns).
I only wish there were 450 kHz I.F. filters available of the same quality that the Murata CFJ455K5 provides. This is the filter Gary DeBock, John Bryant, and I use in our E100s. 73, Guy Atkins Puyallup, WA www.perseus-sdr.blogspot.com -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of [EMAIL PROTECTED] Sent: Monday, September 08, 2008 10:35 PM To: [email protected] Subject: IRCA Digest, Vol 53, Issue 36 ---------------------------------------------------------------------- Date: Mon, 8 Sep 2008 22:01:50 -0700 From: "Dennis Gibson" <[EMAIL PROTECTED]> Subject: [IRCA] My ULR DX Season has Started...2 NEW Ones at Sunset!!!! Robert - I've had a DT-400W for a couple of weeks now. As you said it is extremely sensitive and nulls well but I too am disappointed in the selectivity. Reasonably strong regionals (as far as 300 miles away) sometimes spill over into the next frequency. I guess they decided to put more effort ($$$$) into sensitivity than selectivity. _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.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]
