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Registered Member #3926
Joined: Fri Jun 03 2011, 08:32PM
Location: UK.
Posts: 525
Well anyway my brother decided that he needs a new TV, so he gave me his older one, I'd sat it's from about later 90's, it's very big, would I be able to use the flyback with the circuit on the TV? To power the flyback.
Registered Member #3414
Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
The simple answer is yes.
I've charged a bank of salt water capacitors before just by disconnacting the HV lead from the screen, and connecting an earth to the chassis/ground terminal. I think the EMP that resulted from discharging the capacitors killed the TV though, because it only worked once. (If you try this make sure you use chicken sticks and keep one hand in your pocket, etc.)
The other alternative is to trace the connections, and just use the components you require, but I'm not sure how long it will last/how much abuse it will take before something blows.
Registered Member #3926
Joined: Fri Jun 03 2011, 08:32PM
Location: UK.
Posts: 525
Well I did it before, I tried arcing it to the part where the suction cup is, but nothing happened, I'll try with the TV, it's quite big too, will there be any harmful radiation from the CRT?
Registered Member #3414
Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
DON'T try arcing it to where the suction cup is.
Arc it to either a wire connected to the chassis, or if it doesn't have a chassis, arc it either to a wire connected to the ground on the PCB near the flyback (you should be able to inentify the ground trace) or to a wire connected to the bare wires that are tied to the back of the CRT.
Also, discharge the screen using a chicken stick before disconnecting the suction cup. (I tape a screwdriver to a chicken stick, with a wire connected from the screwdriver blade and to the chassis or the bare wires accross the back of the CRT, then, using the chicken stick, poke the screwdriver under the suction cup until it touches the metal terminals. There is usually a 'pop' if it is still charged.) The CRT acts like a big capacitor, so you can't draw arcs to where the suction cup goes.
The only health risk from the CRT is if it is atill charged up. discharge it as described above. They can remain charged for weeks or months sometimes, and it sounds like your brother has only just stopped using it.
Registered Member #3414
Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
There shouldn't be any radiation from the CRT.
I think that once you've disconnected the suction thing, the CRT no longer forms part of the circuit (although there will still be high voltages present at the 'back end').
I think you'd have to put considerably higher voltages accross the CRT before you get appreciably more radiation than you get in normal operation.
Registered Member #2463
Joined: Wed Nov 11 2009, 03:49AM
Location:
Posts: 1546
TVs around the 90's can produce radiation from the CRT if the circuitry has been damaged or tampered with. Most had a X-Ray shutdown system that crowbarred the processor if the second anode voltage *could* rise too high. Sparking the 2nd anode voltage to ground for experiments is not recommended if the TV will be put back in service. A bad X-Ray protector would shut the TV off or even stop it from powering up.
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I have an old TV
