Quote:
Originally Posted by electroking
Most of the battery type tubes (such as 1R5, 1T4, 1U4, 1U5, etc.)
have 50-mA heaters.
|
OOPS! I grabbed a common portable radio tube, a 1R5 and looked it up, knowing that all of these common tubes draw the same current. Unfortunately, I read the current for the tube above in the manual, a 1R4 which does indeed draw 150 ma heater current.
The conclusion is still the same, these battery radio tubes draw far more current than a a modern DMM can deliver when measuring ohms.
jr