Quote:
Originally Posted by MadMan
"Really need a CRT tester" is kind of misleading. When you test the tube and it shows 'dead' they will say that the tube is 'asleep' and you will not know for sure if the tube is good or bad until you have it plugged into a fully functioning set. Of course, if you had a fully functioning set, you wouldn't need a crt tester. So really, you don't need a crt tester.
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I wake up sleeping CRTs on my B&K 466...at normal settings most wake up in 15 minutes, then you have to readjust cutoff to get correct emission readings....tubes that take more than twice that time I usually increase heater voltage to 1.4X it's rated voltage and let it cool till it wakes up beyond the ~15 second shift after the heater bump.
The shadow mask in color CRTs blocks ~80% of electron emission from reaching the phosphor so a tester designed to test color tubes will have the scale calibrated for color and monochrome tubes that have emission below what is good for color but reasonably above stone dead are usually watchable... knowing your tester and how it's readings correspond to actual performance on color and monochrome tubes is the difference between it being a rough guide/toy and an actual useful instrument.
On that video where shango abused that record at least it was a home recording...those are generally worthless unless the person recorded has been identified as someone famous....the recording may have been priceless to the surviving family but when they allow such a record to leave their family it generally becomes worthless and lost forever.
Shangos methods can be a bit unorthodox but on bad examples of sets that in some cases are barely worth using for parts he can't do much more harm beyond what time and neglect have already done. Depending on the vintage condition and intended use/desired reliability of a set I can respect doing the minimum to make something work....If you are only going to run something 5 minutes a year and it's a nice original example of the thing is a train wreck that isn't worth throwing spare change at a full recap/restore or even any work isn't necessarily needed. Sets of the 60s onwards have good enough caps that if they mostly work then it's perfectly fine to replace the minimum of parts to achieve proper opperation and leave all else alone.