 Posted: Tue Oct 31, 2006 1:38 pm Post subject: Toshiba 2050RE |
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| Hi, Have a Toshiba 21inch colour TV with no vertical deflection. One single bright line across in the middle of the screen. Checked for bad caps and vertical IC LA7837. Found that pump-up supply voltage at Vcc pin8 is only 2 volts. It's suppose to be 24v as per Sanyo IC specification.
I traced pin 8 and found it was connected to another IC M52707SP-A at pin 26. I disconnected all components to this pin and measure the voltage and I got only 2v.Im unable to find any details for this M52707SP-A chip. I understand most Vertical IC recieve its Vcc supply from scanPS. But this one comes from another chip M52707SP-A(Mitsubishi). I do not have the schemetics and at a lost of what to do. Hope someone can point me in the right direction or let me know any other test I can do to pin down the problem. It has taken me 2 weeks to this stage now. Thanks in advance. roger |
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