Re: RCA AR88D Comms Receiver.
You don't need a Q meter to measure the Q of one coil. It's not too bad to cobble together a test rig if you have some other test instruments.
You can do it with a stable sig gen and a spare receiver.
Also, an oscillator doesn't necessarily have to have a high Q resonator in order to run at all, but it does help a lot in cleanliness of theoutput signal (low phase noise). Most valve oscillators are self-biasing. Oscillation builds up until a little bit of grid current causes rectification which self-generates negative bias for the grid and thereby levels off the gain and anode current. They can have quite a bit of excess gain at start-up.
Might be interesting to have a milliammeter in either the anode or cathode path to see what happens on the various ranges.
David
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Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
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