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Old 5th Feb 2023, 5:30 am   #13
dmowziz
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Join Date: Nov 2021
Location: Toronto, Canada
Posts: 131
Default Re: Trio TR2200GX RX Oscillator

Quote:
Originally Posted by Jon_G4MDC View Post
I suppose the collector parallel tuned tuned circuit makes that point pretty high impedance so there can be lots of swing.

I think it might be an idea to knock one up and see what happens.

Hi G4MDC,
Did you still attempt in making one?

The 1st attachment is the schematic of a crystal oscillator (10 MHz and 12 MHz).

As can be seen, the only capacitor needed is that to be used to view on a spectrum Analyzer. The crystal is acting like a series RL
It does not look like an oscillator but it sure does oscillate.
The base voltage is from a potentiometer

You can attempt if you have a genuine 2N3904 (Although I used a 2N3904BU but any genuine 2N3904 should work)

Alot of harmonics : The negative resistance is alot more than crystal ESR
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