Amongst other things it depends on the freq of the LO, the physical
distance between the SA605s.

What freq is the LO ?

How far apart are the SA605s ?

-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!