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What does .75mA correspond to on the emissions good bad scale?
The quick drop is a life test. A life test is supposed to predict how long into the future the tube will last in regular usage, but tells nothing about it's present condition. The emission test tells about it's present condition, but tells nothing about how long the tube has left.
A CRT can have a lousy life test and still be usable as long as you don't put a ton of hours on the set. Low emissions (assuming some still exists) can also be compensated for by adding a brightener or increasing HV. Also CRTs that have been dormant for over a decade often are asleep...As in the cathodes have been contaminated with gas, and the tube needs to be ran at 1.4X the heater voltage for 5 minutes-5 hours to boil off the gas contamination and restore normal emissions (if emissions are low run it at higher heater voltage for a while on the tester, and see if it improves, and be sure to let it sit at high heater for at least a good 10 minutes after the emissions improves).
A picture of the meter would be helpful to those of us with different tube testers with different scales.
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