Question about Philips Magnavox 27MS343S 27" TV

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Tv set won't start up

Power suply only gives 40 vdc at main output then shuts off, I try changing power reg. STRS6656, no change, I checked all resistors and capacitors on the power supply area and all seems to be ok, I disconnect all output diodes, letting only the main output and still giving 40 vdc for a second and then shuts down, I got tired trying to find some thing wrong, does anybody may had have the same problem? any help wold be very apreciated.

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Re: tv set won't start up

As your reg. output is 40v & you have checked every possible things responsible for it. my suggetion is that first you isolate power supply from hor.section & see if power supply output is ok. if it is ok then check for short & leakage in h/output like 1 hor.output tr. 2 diode or cap in eht winding. 3 check for print near eht transformer. 4 disconnect yoke connector & check . 5 & finally eht or flyback transformer.

Posted on Oct 01, 2007

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