Varactor tuning diodes.
 

Hello,

I have a general question regarding tuning diodes:
Does the oscillation voltage alter their capacitance, or is capacitance a
slow changing value - like resistance and PIN diodes?

The reason I ask is that I am spicing (simulation) a VCO I wish to build
(wide range 140-240MHz) and get an oscillation voltage of 20 volts peak
(maybe the Q is too high). This high oscillation voltage would easily swamp
the tuning voltage, 3-15 volts, and forward bias the diode itself.

If anyone wishs to reply directly they must remove the "xxx" from the return
address or write to:
james dot fenech at nec dot com dot au

Thanks,
James.