Thanks, Rick. The 500 Hz makes sense, since some of the modes are over 250 Hz. I have the twin passband, too, but it's just not as effective as I'd like. The APF/ANF on the non-Pro works great on CW, and with just the APF on narrow, I can narrow the passband down to around 30 Hz, but that doesn't do me much good for PSK hi hi! I should have waited for the Pro to come out!
Tnx es 73 Dave KB3MOW > Hi Dave, > > Yes, the narrower filters will help a great deal. I have an ICOM rig > that needs to be centered on 1500 Hz when operating in SSB modes so I > try and move them to that point if I can. Then I have DSP filters that > enable me to close the "window" as tight as I need to. I also have Twin > PBT which enables me to dial each side of the interference. But the > actual bandpass filters are much more effective with the really strong > signals. > > If I could only have one additional filter than the stock SSB filter, I > would go for the 500 Hz filter since it is very useful for CW use as > well as narrow to medium digital modes. I have a 270 Hz crystal filter > in my Kenwood TS-440SAT that I find rather narrow although some might > prefer that for CW. > > If you go narrower than 500 Hz, you can not use a number of digital > modes that are around or slightly under 500 Hz, but may not fit well > into at 250 Hz bandpass. > > 73, > > Rick, KV9U > > Dave wrote: >> 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 >> >> > >
