We generally use 300 Hz filters for PSK125 and they are too wide. There is no substitute for good narrow Xtal filters. I don't understand how you can try to work PSK31 (50 Hz bandwidth) with a 2.7 kHz filter. That is against all logic (and math).
We recommand using the narrowest filters you can get for pskmail. That is the only way to fight Pactor QRM. It helps to use the passband shift and use the sweet spot of the rig at 1500 Hz (we use an Icom 756). Our PI4TUE server has good performance with that, provided you get the filter as narrow as possible (this is for PSK125, which is 4x the bandwidth of PSK31...). A 250 Hz Xtal filter is wide enough for PSK125. 73, Rein EA/PA0R/P > -----Ursprüngliche Nachricht----- > Von: digitalradio@yahoogroups.com > Gesendet: 07.03.07 19:53:26 > An: digitalradio@yahoogroups.com > Betreff: [digitalradio] narrow filters/PSK > > Has anyone tried using either a 250 Hz or 500 Hz filter for PSK31 > reception? My Icom IC-746 (non-Pro) has no filters installed, and is > wide as a barn door on USB for PSK31. I wondered if either of these > filters would help, or would they be too narrow? > > The pass-band shift does a fair job of eliminating QRM from one side > or the other of the selected frequency, but when there are two very > strong signals within 2 Khz on each side at the same time, they just > aren't effective on both. > > Any input appreciated! > > Thanks in advance es 73 > Dave > KB3MOW > > > > > > > Announce your digital presence via our DX Cluster > telnet://cluster.dynalias.org > > Our other groups: > > http://groups.yahoo.com/group/dxlist/ > http://groups.yahoo.com/group/themixwgroup > http://groups.yahoo.com/group/contesting > http://groups.yahoo.com/group/wnyar > http://groups.yahoo.com/group/Omnibus97 > > > Yahoo! Groups Links > > > > -- http://pa0r.blogspirit.com ------------------------ Yahoo! Groups Sponsor --------------------~--> Something is new at Yahoo! Groups. Check out the enhanced email design. http://us.click.yahoo.com/kOt0.A/gOaOAA/yQLSAA/ELTolB/TM --------------------------------------------------------------------~-> Announce your digital presence via our DX Cluster telnet://cluster.dynalias.org Our other groups: http://groups.yahoo.com/group/dxlist/ http://groups.yahoo.com/group/themixwgroup http://groups.yahoo.com/group/contesting http://groups.yahoo.com/group/wnyar http://groups.yahoo.com/group/Omnibus97 Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
