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Old 14th Jan 2018, 11:49 am   #46
MrBungle
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Join Date: Jun 2016
Location: London, UK.
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Default Re: The Best GDO Ever Made?

Did some reading about negative resistance last night and it actually makes a lot of sense. If you have a voltage divider with one resistor as a negative resistance then you have a voltage divider with gain and phase shift (an amplifier). Add a tuned network to this (LC/crystal) with a matching phase shift at the oscillation frequency and it completes the Barkhausen criteria. FET as a transconductance amplifier gives V is proportional to conductance which is the reciprocal of resistance.

This may be completely wrong as it was at 3AM while I was waiting in the hospital with a wife with a swollen up head in a bad mood (had a wisdom tooth out on Thursday and it went a bit wrong)
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