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Old March 9th 07, 10:11 PM posted to rec.radio.amateur.homebrew
MarkAren MarkAren is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 47
Default One crystal with several mixers?

I vote for the 4 way resistive splitter
http://www.microwaves101.com/encyclo..._splitters.cfm fed
with lots of ergs from a gently tickled Xtal osc and sutiable
buffering. Terminate each limb in 50 ohms near each 605 and feed with
50 ohm microstrip from the central distribution point (buffer).

-Mark

On Mar 8, 8:18 am, wrote:
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!