This is a generic problem: How much must a user on an adjacent frequency take into account that his neighbor is unable or unwilling to operate at only the bandwidth necessary for an emission? Typically, we see complaints (here!) that while we're operating PSK 31 an emission 500 Hz away blows us out of the water, a circumstance which, if we used only the bandwidth necessary, would rarely arise.
With my FT-857, a 300 Hz IF filter and a 60 Hz audio DSP setting, I can run PSK-31 as close as 100 Hz or so to a carrier, mark or space. A KAM TNC hardware PSK modem can handle a lot of off-frequency noise, too. A K3 or a Flexradio would let me run that narrow or better at the IF and never notice the guy I'm next to. How much account do I need to take of his receiver bandwidth? As I say; a generic problem. Cortland KA5S > [Original Message] > From: John Becker, WØJAB <w0...@big-river.net> > To: <digitalradio@yahoogroups.com> > Date: 11/25/2009 12:56:27 PM > Subject: Re: [digitalradio]my last word > > Makes a lot of sense.... > > Let me try it this way - if I'm operating with my mark tone > on a freq between your mark and space you never bother > my QSO. Why is that the every time you hear a tone > close to your operating freq it's QRM. ------------------------------------ Suggested frequencies for calling CQ with experimental digital modes = 3584,10147, 14074 USB on your dial plus 1000Hz on waterfall. Announce your digital presence via our Interactive Sked Pages at http://www.obriensweb.com/sked 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: digitalradio-dig...@yahoogroups.com digitalradio-fullfeatu...@yahoogroups.com <*> To unsubscribe from this group, send an email to: digitalradio-unsubscr...@yahoogroups.com <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
