I have 8 pole 400 Hz filters in my K3s's, not 500 Hz as well as 250 Hz. According to W0YK's presentation linked below the 400 filter has a bandwidth of 435 and the 250 filter has a bandwidth of 370. This data is for 8 pole crystal filters made by Inrad, I am not sure what filters Elecraft currently sells.
http://www.nccc.cc/archived_meetings/pdf/K3%20Filters,%20Jan%202009.pdf John KK9A Jim Brown K9YC wrote: On 1/27/2021 12:14 PM, john at kk9a.com wrote: > FWIW, I have both the 400 and 250 8 pole filters. If money is an issue, > I believe that there is very little bandwidth difference between the two. I have both as well in all my radios. I can clearly hear the difference when switching between them. I mostly use the 250 Hz filter for CW and the 500 Hz filter for RTTY. 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
