|
Your CRT MAY just be asleep. We have seen this MANY times. A CRT will show very low emission...at FIRST_-when it is first checked after sitting for MANY years. I recently saw this on a 22 inch late 70's BW tube. it showed VERY low--at first. So...I 'gassed it a bit"--by turning the filament to about 7.5 volts....and it did NOT take long...before the meter on my CR-70 (which has a MUCH bagger "bad' range than yours does), was reading into the "good" range. After a few miutes of this...I was then able to reduce the filament to 6.3 volts and the tube STILL showed int the good range. before too long..it would show good at FIVE volts on the filament !! And life test holds WELL...moving just a BIT--and NOT into the red--after 20 seconds.
So..DO THIS...with yoiur tube. Crank the filament to about 7-8 volts...and let it sit tihs way--for at least five minutes. If you STILL get no better results...go to 8.5 volts for 10 minutes. If after THAT...the meter STILL does not go up apprecibly..the tube may indeed be gone. but I WOULD try to save it first--CRT's Are NOT that easy to come by anymore !!
|