Quote:
Originally Posted by Electronic M
So CRTs have this thing in them called a getter that is made of highly reactive metals that soaks up gas molecules. The cathode that makes the electron beam is also made of highly reactive metals, so when the CRT isn't run for a prolonged period and starts to act like a getter and react with gas forming insulative oxides on the cathode that block emissions. When you run the tube you boil those gas molecules off the cathode...The longer you cook the cathode at normal or slightly elevated heater voltage while drawing test or operating cathode current the larger the percentage of the accumulated gas leaves. The tubes emissions will wake up as it cooks.
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Okay. Thanks for the explanation. To clarify, when you say "while drawing test or operating cathode current," do you mean that you leave the CRT tester on one of the settings (if so, which setting?) while simultaneously raising the filament voltage?
Thing is, I have a CR70, not one of the B&K units, so I'm not sure what the exact analog of your suggested procedure would be. I can set the filament voltage higher and let it sit there, but I'm not sure how I would "drawing test or operating cathode current."