Yes, that is what the theory says, but I think there is variation in filter implementations such that some 8 pole filters ring worse than others.
With the DSP, one approach is to use a 5 pole filter to get a less ringy first filter followed by the DSP which adds the extra selectivity to achieve the ultimate rejection and elimination of signals outside the roofing filter. This might give great selectivity with less ringing than trying to put all that selectivity in the crystal filter. - Keith N1AS - - K2 5411.ssb.100 - - K3 Wave 3 - -----Original Message----- From: Alan Bloom [mailto:[EMAIL PROTECTED] An 8-pole filter should have more ringing than a 5-pole filter of the same bandwidth and ripple. That's because the loaded Q of each pole (crystal) is higher (bandwidth of each pole is narrower). You can think of it as each crystal covering 1/8 of the bandwidth rather than 1/5, although that's an oversimplification. _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
