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Old March 8th 07, 01:23 AM posted to rec.radio.amateur.homebrew
W3JDR W3JDR is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 44
Default One crystal with several mixers?

Either approach will work

Joe
W3JDR


wrote in message
oups.com...
I'm designing a box that will use four SA605 receiver/mixer chips that
all need the same crystal reference. Even with all the good
application notes for the SA605, I'm not sure how to do this. Do I
build a Colpitts oscillator from transistors, buffer it, and then use
this output as an "external LO" for the mixers? Or do I connect up
the crystal to the SA605 oscillator pins as usual and then tap off of
this for the other chips? Using a function generator as an external
LO, I get the best results injecting a 300mVpp sine wave, if that is
useful.

Thank you!