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Has anyone fixed a Model 680 shadowgraph. I tried the usual hints from the " repair bench" with no results. the vane is free and coil shows 500 ohms resistance. #85 tube is good with 70 volts plate voltage. Thanks in advance Norman
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Any chance that the bar magnet has become demagnetized?
500 ohms sounds low to me for the coil resistance - typically they're >1K.
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Even if 500 ohm, still should react.
I second the magnet thought.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Just for grins take a 9v battery - to the chassis and + to the grid cap of the 85. Should cause the vane to deflect.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
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Thank you folks for the hints. Norman