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Old March 14th 07, 11:12 PM posted to rec.radio.amateur.homebrew,sci.electronics.basics,sci.electronics.design
Ian Jackson Ian Jackson is offline
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First recorded activity by RadioBanter: Oct 2006
Posts: 89
Default VCXO frequency isn't high enough

In message , Anthony Fremont
writes
Anthony Fremont wrote:

Doodling with reactance formulas, it appears that 20uH (coincidence?)
would offset 100pF of capacitance fairly well by having a an opposing
reactance (well resistance at this point) of about 450 Ohms at


s/.well resistance at this point.//
It's just inductive reactance, I need more coffee. ;-)

3581kHz, the same as 100pF. I'll try putting the coil I made in
parallel and see what happens. Hopefully it won't short the
oscillator and kill my 15 year old NE602, I only have two spares.


Should I be afraid to do this? Does it need something to block DC current?



If you do try an inductor across the crystal, make sure that you still
do have a DC blocking capacitor somewhere in the path to ground (as
provided by the existing C2 trimmer).
Ian.
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