On Fri, Feb 10, 2012 at 3:52 PM, Bob Camp <li...@rtty.us> wrote: > Hi > > I think you will need some sort of analog detector to get what you are > looking for.
I don't think it needs to be analog. For example you can xor the two 10MHz signals and then sample the digital xor output then deduce its duty cycle by counting how many samples are 1 and how many are 0. You'd expect an equal number if there is a phase lock. Might be best to sample a-periodically at random. Many designs put a low pass filter on the XOR but I think random polling allows the software to adjust the time constant and is cheaper to implement. I think you'd have the latch the xor in a flipflop as it would move to fast for a uP to read. Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.