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Old 10-10-2015, 05:22 PM
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Josef Josef is offline
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Join Date: Mar 2008
Location: Vienna
Posts: 134
Smoke is never healthy for old TVs

Good evening!
Unfortunately the set started and smelling bad while I was watching a movie last fall. At first I thought the high voltage transformer caused the problem because the picture went unstable for a moment .When I took the chassis out of the cabinet I followed my nose and recognized that the main switch was burned out. This power switch is underrated in my opinion and often causes problems in these TV sets. I reconsidered a lot how to repair this defect as good and original as possible. I came to the conclusion that making a bracket and using the switch of the successor TV sets would be the best solution. This Marquardt switch is a German high quality product which works for many ages usually. It will also be possible to replace the contacts from the switch because these switches are still available brand new with higher current ratings but they have knobs instead of claws. It is possible to screw the switch apart and replace the more than 50 years old 1 Amp contacts with brand new 2 Amp rated parts. Never the less I used the old contacts because it is possible to replace them anytime. What sounds easy turned out to be really a lot of work to do- you could also call it a PITA . The reason was that I want to make the switch work in combination with the push button assembly. When I pushed the off button the first time the required force was much too high. I removed one turn of the spring that is built in the switch. This modification reduced the required force to switch a lot. Now I was able to screw everything together and test the whole thing. The push button assembly works in the following way: As soon as the off button is pressed the switch is pushed into the off position. The more interesting part is that a pull spring is set and locked under tension at the same time. If any button that is supposed to turn the set on like AM, FM or PU is pressed, the push button assembly sets the pull spring free. The spring pulls the switch to the on position and the best thing is: This modification could have done with the same materials when the set was new. All added parts are handmade by myself. Please don't ask how long it took me to make the whole thing work as good as it does now

Greetings Josef
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