My Sharp TV Model 25F-M40 is dead.?
This tv is about 10 years old, which I would ilke to repair.
I replaced several parts, horizontal output driver and transistor, SCR for switching power supply, some diodes, several capacitors in the power supply circuit.
Originally fuse was burning out. Now it is continuously clicking which seems to be coming from flyback transformer.
When I check the voltage at the output of scr it is fluctuating between 85vdc and 150vdc.
A friend of mine tells me flyback transformer needs replacement.
I checked all the resistance readings on its windings with a special ohms meter, they all seems to be as indicated in the service manual.
Obviously there are no oscillations and therefore no low volatge dc outputs. No High Voltage output either.
I believe flyback transformer needs air gap adjustment by using two plastic adjustment screws, so I can get oscillations, and then voltage outputs.
I have the sam photofact service manual.
I would appreciate any thoughts.
Thanks in advance
If SCR damaged usually the R fuse near this SCR is also damaged, and please don’t replace it with ordinary small R, I think the problem is still around the Primary area. But I’m not sure.
8/29/10 Garage Sale Find- Motorola SH20N Stereo Record Player
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