Phil and Chen, Thanks! I thought it looked like crystal filter performance but was thinking it was synthesized. This looks like a much better system than Flex's QSD. I wonder how long it will be before Flex goes to the same system? Phase noise and BDR have been Flex's weak links IMHO.
I just located the Perseus user manual so will do some reading on it. For anyone interested: http://microtelecom.it/perseus/perseususermanual-en12.pdf 73, Bill On Thu, Dec 4, 2008 at 3:30 PM, Kok Chen <[EMAIL PROTECTED]> wrote: > > On Dec 4, 2008, at 11:23 AM, Bill W4ZV wrote: > >> Have you described how you achieved this somewhere? > > > Bill, > > I suspect it is because there is no synthesizer in his receiver. Everything > comes off of a single crystal, and as you decimate, the noise from the > oscillator becomes even narrower. > > All the other "oscillators" are numerical and can be made as noise free as > there are processor cycles. Even in cocoaModem (2.4 kc passband digital > mode stuff for the Mac OS X), I had use a 24 bit since/cosine generator, > using 12-bit table lookups and the double angle trig formula to get 24 bits > of output resolution. > > "Phase noise" is a hardware artifact :-) :-) > > Vy 73 > Chen, W7AY > > _______________________________________________ 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
