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Couple of Compact CRT questions

It's called a "Minus Screwdriver" because after discharging the flyback transformer a couple of times will chip the blade's tip and it will be useless as a screwdriver after that.

Unless you you got an electric grinding stone wheel to grind the tip back into shape.
What awful chinese foundry did your screwdrivers come from?? I've used the same Fuller screwdriver for discharging dozens of times and I don't even have pitting on the blade.

 
out of curiosity .....can it be said then that ANY crt will have fully discharged after 1,2 ,3  even 4 weeks,  being plugged out?

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im terrified of those flyback transformers and always discharge them, even on color classic's , classic's etc etc

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is there any situation, weather it be from faulty components etc etc , where the crt remains charged indefinitely ??

 
Falen5 - Given time the energy stored in the caps will dissipate into nothingness. But to do it on its own takes time. Shorting out the Flyback Transformer high voltage line with ground dissipates the energy immediately.

The problem (depending on the Classic Mac) is C1, its the cap that supplies the transformer with a high amperage / low voltage energy which the transformer converts to high voltage / low amperage. Don't let the low voltage of C1 fool you, it has enough amperage to knock you to the floor like T1 does with its voltage!

When you turn off the Mac, C1 is still charged up even with no power going to it. The good thing is that the energy will reverse its flow and fade away but that takes days to do. So shorting out T1's high voltage line immediately drains out C1, making it safe for you to deal with the CRT and Analog Board.

 
Hello, I'm going to disassemble my old SE/30 to change the front bezel with that of another SE/30 (in a better condition). Once I discharged the CRT, can I proceed safely or I need to take some safety precautions, for example, in managing the transformer or something else? Thank you a lot.

 
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