Re: Soldering a Broken TV

meow2222@xxxxxxxxx wrote:
StarBaseONE2@xxxxxxxxx wrote:


Always best to discharge! you can use a simple flathead screwdriver
with an alligator clip. Clip it to the screwdriver and clip it to DAG
Ground... it will be a braid of wire attached to the CRT tube slide
flathead screw driver in under the anode cap that runs to the flyback
transformer. It will look like a large suction cup attached to the
picture tube.. You will hear a 'pop' as the HV discharges. Then it will
be ready to pull that board. I would still be leary of the filter caps
though!


This is not safe.

1. Alligator clips come off very readily, and screwdrivers dont
insulate to 25kV. There is also the q of what the clip is touching
after its come off, it may be your metal trouser fly. :)
2. The OP may think you mean the braid that connects to the tube base
pcb, and aquadag braid to chassis is prone to coming disocnnected in
some set designs, so again this may fail at times.
3. Finally a single zap does not discharge the CRT, it typically takes
3 goes.
4. And lastly, reservoir caps must be discharged too. They are a good
deal more dangerous than CRT EHT, which is usualy not fatal and is more
or less insulated. Reservoirs OTOH are kill capable, and conductive
paths route their energy to who knows where on the board. And typically
a repair will involve handling the main board - often with both hands,
which is where the danger comes in. A cap full of 330v across the 2
hands is not something to volunteer for.

Maybe the OP should read up on Darwin Awards.


NT



It may not be "safe" but I've been doing it that way for 15 years and never had a problem with it. Screwdriver with a wire wrapped around it connected to the dag strap. Most of the other caps discharge themselves but I stick a screwdriver across the big ones just to make sure.
.

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