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Can you test tubes with an ohmmeter for more than shorts?


I thought there might have been a specific ohm range between pins.sensors I test at work have them I have to call manufacture for specifics. Like an igniter for heater 50 to 75 ohm is good range,will work above 75 ohm but ready to pop.
 
I thought there might have been a specific ohm range between pins.sensors I test at work have them I have to call manufacture for specifics. Like an igniter for heater 50 to 75 ohm is good range,will work above 75 ohm but ready to pop.

Tubes should show either a complete open circuit or a dead short depending what elements are being checked. Filaments should show a nearly dead short while plate to grid should be infinity. Some tubes may have a grid connected to the cathode and will show a short. You need to know the pinouts of the tube to be sure.
 
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I bought an Eico 350 tube tester about 15 years ago.... The only good way to check vacuum tubes or also known as valves. The tester will load the tube properly with correct voltages and measure resistances and drops. The only good way to check a tube!
If a tube has a dull white spot or spots then it has become gaseous, the getter has been oxidized. This is a visual check!
Vacuum tubes are consumables so they need to be replaced every so often and not many are made nowadays. Thankfully Guitar amps are still being made!
And I do remember Radio Shack had tube checkers in the store and some drug stores! Where did all this machinery go?

73 mechanic
 
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