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Old October 1st 08, 01:13 AM posted to rec.radio.amateur.homebrew
Tim Wescott Tim Wescott is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 202
Default Reference oscillator frequency = IF?

Joel Koltner wrote:
I'm thinking it'd be a rather poor idea to make a reference oscillator for a
DDS (or PLL) equal in frequency to an IF somewhere in your radio... right?
Since you're just asking for it to get into the IF itself?

In the ideal world, would one choose reference oscillator frequencies that
weren't harmonically related to IFs? I've seen those "IF planning"
spreadsheets (that calculator where mixer spurs are going to fall), and such a
choice seems like a good start.


I would certainly avoid it. With thorough enough shielding you can keep
just about any signal out of any circuit, but there's no need to tempt fate.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html