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Old 01-12-2019, 06:44 AM   #10
CuriousJohn
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Join Date: Dec 2018
City & State: Britain
My Country: Great Britain
Line Voltage: 230VAC 50HZ
I'm a: Hobbyist Tech
Posts: 21
Default Re: Bush idlcd26tv22hd 17PW15-8 issue

Quote:
Originally Posted by R_J View Post
So IC802 is a L6562 and not a IRF7314 as on the schematic? Pin 1 will likely be low as the voltage comes from +400v but since the pfc booster is not working, that voltage would only be around 340v
If those C805 & C870,C808 are small electrolytics, they could be bad.
Q803 is driven by ic802 at 70khz, so yes it does switch the primary of TR806 to ground BUT at 70khz, that action boosts the 340 volts to 400 volts on the other side of D824, Thats why the voltage on C819 is important to check as it wil tell you if the pfc is working or not
Yeah IC802 is a L6562 not the dual mosfet shown on schematic.

You just answered my next question lol as was wondering what freq it was switching at, going to get an old scope out later been a few years its time I got smarter only so much can do with a multimeter!
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