JamesQB |
Posted: Sun Mar 05, 2006 8:08 am Post subject: |
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The wire wrapped around the tube you refer to sounds like the degaussing coil. This is used to remove any latent magnetic fields from the CRT (otherwise you can eventually get the effect you get if you place a magnet near the screen).
If just tapping the set induces the fault, then it's either a bad connection, a dry solder joint or in rare cases it can be caused by a component with the leg loose inside its body - much harder to trace. I've even had components that appear to have perfect solder joints bonding their legs to the PCB, yet you can pull the component completely out of the PCB, leaving the nice solder joints in place! This is caused by the solder no longer being bonded to the legs or a coating on the legs having come off, so only the coating is bonded to the solder, not the legs.
Does the set have upright subpanels pushed into slots on the mainboard, or pushed into sockets? Cleaning any connections like that is a good idea. For the tech, all he should need to do is get tapping different areas of the board in the set until he can induce the fault, thereby narrowing down where the trouble is. I wouldn't recommend you to do this if you're not savvy as the set needs to be running of course and there are lots of high voltages about (even with the set unplugged, for days afterwards sometimes).
Shouldn't be much trouble to fix this I wouldn't have thought, nothing better than a set that needs knocking to cure it or bring a fault about! |
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