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**R_J** · 10-26-2019, 10:01 AM

The PFC circuit is not being turned on. If it was, the voltage on the main cap would icrease. I suspect you are not getting 20v VCC, this VCC voltage also supplies ic902 pin6.
The 10 volts on IC909 pin 8 is supplied by it's internal startup cell. Check the voltage on Q903, The emitter should have ~25vdc, the base is controlled by optocoupler IC905. When IC905 is ON, pin4 will be low turning on Q903 which supplies the +20dc for IC909 and IC902 VCC

10-26-2019, 10:01 AM	#32
R_J Badcaps Veteran Join Date: Jun 2012 City & State: ☻ My Country: Canada I'm a: Professional Tech Posts: 6,578	Re: Philips 32PFL3606/58 The PFC circuit is not being turned on. If it was, the voltage on the main cap would icrease. I suspect you are not getting 20v VCC, this VCC voltage also supplies ic902 pin6. The 10 volts on IC909 pin 8 is supplied by it's internal startup cell. Check the voltage on Q903, The emitter should have ~25vdc, the base is controlled by optocoupler IC905. When IC905 is ON, pin4 will be low turning on Q903 which supplies the +20dc for IC909 and IC902 VCC Last edited by R_J; 10-26-2019 at 10:11 AM..