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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html