|
Philco 680 Shadograph.
02-02-2018, 10:50 PM
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
02-02-2018, 10:56 PM
Any chance that the bar magnet has become demagnetized?
500 ohms sounds low to me for the coil resistance - typically they're >1K. 
02-02-2018, 11:14 PM
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.
02-03-2018, 10:08 AM
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
« Next Oldest | Next Newest »
Users browsing this thread: 2 Guest(s) |
|
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
