[time-nuts] reference oscillator input circuit

Rick Karlquist richard at karlquist.com
Wed Dec 8 17:28:36 UTC 2010


jimlux wrote:
> I'm looking for suggestions on a general circuit that can be used to
> receive an external frequency reference (nominally a real clean sine
> wave at, say, 10 MHz, although up to 100 MHz is possible) and turn it
> into a "real clean" square wave.  Galvanic isolation is a plus (a
> transformer or capacitor would probably do that).

In the 5071A at 80 MHz, we capacitively coupled a sine wave into
a 74AC series logic gate, that had DC bias resistors to hold
it at half the supply voltage.

Rick Karlquist





More information about the Time-nuts_lists.febo.com mailing list