Hi Small signal wise a prescaler looks like a divider.
Below some threshold you (hopefully) get nothing. Above that point you get various sorts of garbage (which could include self oscillation) unrelated to the input frequency. Past another point you get an increasingly solid divide out. The magic points are level, load impedance, source impedance, temperature, and supply voltage dependant. Bob -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Peter Monta Sent: Thursday, July 28, 2011 4:15 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Anybody experienced in using a prescaler as a wideband preamp? Paul Swed writes: > I agree this does not make sense. There is a divider in the way so its not a > preamp. I'll bite: what does a small-signal model of a prescaler look like? As a guess, it might be a (flat? highpass?) attenuator (with a great deal of loss) up to some threshold amplitude, then above that one would get the divided output. But that's with a pure-tone stimulus. Perhaps a prescaler could be made to act as a kind of preamp-plus-mixer by pumping it with an LO just at threshold, then adding in the input signal. Likely enough, though, there are better ways to accomplish whatever the system-level goal is. Cheers, Peter _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
