Lets really mess with contesters minds....give them a report of "20db over S2."
grandmaw Susan If you don't change direction you WILL arrive exactly where you're headed!! Susan Meckley, Skipper W7KFI-mm AFA9SM USSV DHARMA --- On Thu, 7/15/10, Wayne Burdick <[email protected]> wrote: > From: Wayne Burdick <[email protected]> > Subject: Re: [Elecraft] Let's Try This Again -- was "[K3] ... A 750 Hz, > 8-Pole ... Filter?" > To: "Jim Brown" <[email protected]> > Cc: "[email protected]" <[email protected]> > Date: Thursday, July 15, 2010, 8:01 AM > It *is* difficult to build very > narrow 8-pole filters with low loss. > That's one reason Elecraft offers a 5-pole, 200-Hz unit. > > 5 poles is entirely adequate at these narrow widths. Our > 2-kHz IMD > dynamic range using the 200-Hz filter is outstanding. > > We've had some requests to offer a 270 or 300-Hz 5-pole > filter, which > would be better optimized for narrow-shift RTTY than the > 200-Hz > filter. We're also considering a dual-passband filter > (500/270 or > 500/300) that would fit in one slot. > > 73, > Wayne > N6KR > > > On Jul 15, 2010, at 10:18 AM, Jim Brown wrote: > > > On Thu, 15 Jul 2010 14:53:10 +0100, Ian White GM3SEK > wrote: > > > >> Agreed. 250-270Hz would be the "sweet spot" for an > 8-pole filter, to > >> guarantee good sales for the manufacturer *and* > good performance > >> for a > >> range of users in heavy QRM. > > > >> Now let's see if Inrad or Elecraft take the bait > :-) > > > > Hang on a minute, guys. Inrad builds a nominal 250 Hz > filter, Elecraft > > tests and re-sells it, and we buy it, because we've > agreed that it's a > > sweet spot operationally. > > > > The issue is that it's wider than than at the -3dB > points. So the > > problem appears to be that it's pretty difficult to > build an 8-pole > > 250 > > Hz filter at 8.8 MHz, and that Inrad has given up on > doing better. > > > > 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 > > ______________________________________________________________ > 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 > ______________________________________________________________ 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
