> Note also that, based on my limited experience, most > commercial mixer implementations use a much faster > beat note: 10, 100 Hz, even 1 kHz. A faster beat note > may help your concern #1 above, and #2 below.
Ulrich, One thing I forgot to mention earlier -- there is another advantage in using a higher beat frequency; that is, you can average many more samples in less time. In all your examples you seem to imply a 1 Hz beat and an 'instant' measurement in just one second. I think in the real world phase comparators use both a higher beat frequency and a longer measurement reporting time. If you instead use a 100 Hz beat it seems to me you'd get 100x more zero crossings and any white noise would then average down by sqrt(100), or 10x. Furthermore, if you wait 10 or 100 seconds for a final result instead of 1 second, that's another order of magnitude in sensitivity. I would guess a lot of your instrumentation noise is white so you'd get good leverage here. I could be wrong about all this, but as you continue to experiment, please try several different beat frequencies and averaging periods and let us know what you find. /tvb _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
