Found a nice article on a 12AU7(ECC82) vfo here, decided to try out the circuit using less lethal voltages (I had my fair share of electric shocks if you know what I mean).
Here's the prototype:
...admire the beautifull wiring work...
and circuit...you can find a clear one in the article link provided above.
It works! The only hard part is to make the a coil for it. Mine was done with the cientific methot of trial and error...oscilates around 800-1200khz but I intend to make one for 5-5.5Mhz.
This was just a proof of concept but working with 12V supply and no buffer it can deliver about 0dBm measured from my NCY (Not Calibrated Yet) AD8307 power meter.
It takes a little to get into oscillation due to valve warming as you can see in the video:
Having time and a nice box to put it, looks like a nice little external vfo for one of my vintage HF radios....one of this days....
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