This tv flickered for a few weeks and then no picture. sound is ok.
I google search and found someone else with same trouble.
They said they had 81 volts on the cvb4200 power supply board.
I checked mine and had the same thing.
I got a new cvb42001 board from shop jimmy.
I checked its 4 outputs to (i think, the backlight) and was 25 vdc.
so
I installed the board and still no picture. sound was ok
I rechecked the 4 outputs to (i think the back light) and is now 81 volts.
i don't see any bad caps and nothing smells like a toasted transistor.
I don't know what to check next. i tried to check ohms on the 4 wires that I think go to the back light but i get no reading. I think because Is diodes?
Personal info:
I know what a voltage divider is and how a transistor works. I can sketch a simple amplifier circuit but I am not a electronic tech. I worked for 10 years as a digital controls technician and have assembled several dozen computers over the years since my first 386.
I google search and found someone else with same trouble.
They said they had 81 volts on the cvb4200 power supply board.
I checked mine and had the same thing.
I got a new cvb42001 board from shop jimmy.
I checked its 4 outputs to (i think, the backlight) and was 25 vdc.
so
I installed the board and still no picture. sound was ok
I rechecked the 4 outputs to (i think the back light) and is now 81 volts.
i don't see any bad caps and nothing smells like a toasted transistor.
I don't know what to check next. i tried to check ohms on the 4 wires that I think go to the back light but i get no reading. I think because Is diodes?
Personal info:
I know what a voltage divider is and how a transistor works. I can sketch a simple amplifier circuit but I am not a electronic tech. I worked for 10 years as a digital controls technician and have assembled several dozen computers over the years since my first 386.
Attached Files
Comment