Hi, I ordered and use the 400 for RTTY, I suspect the 250 is a bit to narrow. -- Thanks and 73's, For equipment, and software setups and reviews see: www.nk7z.net for MixW support see; http://groups.yahoo.com/neo/groups/mixw/info for Dopplergram information see: http://groups.yahoo.com/neo/groups/dopplergram/info for MM-SSTV see: http://groups.yahoo.com/neo/groups/MM-SSTV/info
On Sun, 2015-02-15 at 22:02 -0500, Dick via Elecraft wrote: > Hi Guys, > > I'd appreciate your thoughts on the best roofing filter: 250hz vs. 400hz, > for RTTY contest conditions. > > While I really like the K3 on RTTY, I believe improvement can be made to > my K3 RTTY reception. Some contesters have told me that they use the 250hz > roofing filter exclusively when operating RTTY contests. Since the actual > bandwidth of the 250hz roffer filter is close to 370hz, and RTTY signals > are typically about 370hz wide, then the 250hz roofer along with a 400 or > 500hz DSP setting should be close to ideal when maximum selectivity is > needed. However, on both of my K3's, when I switch from the 400hz roofer to > the > 250hz roofer, the RTTY signal is decoded a lot less often, about 25% less > often. It doesn't seem like the 400hz roofer should decode 25% more often > than the 250hz roofer. (but perhaps that's normal?) > > > Perhaps there is a receiver setting change I can make to the K3 that will > improve RTTY decoding when using the 250hz roofer? I've tried various > shift settings when the 250hz roofer is engaged and sometimes it improves > RTTY > reception, but not consistantly. Perhaps there's a setting change I can > make to MMTTY? > By the way, I'm using both MMTTY and 2Tone software's for decoding RTTY, > with basically the same results when the 250hz roofer is engaged. > > > Thanks in advance for your thoughts. > > 73, > Dick- K9OM > > > > > ______________________________________________________________ > 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] ______________________________________________________________ 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]
