My Sharp TV Model 25F-M40 is dead.?

Question

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

Answer 1

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.

Answer 2

I went to Sharp's technical support site and there is no listing for your TV.

http://www.sharpusa.com/products/support/view_all_models/0,2326,27,00.html

I would suggest that you get a new TV anyway, I mean to replace parts repeatedly after awhile will result in money lost that could have been put toward a new TV in the first place. Sometimes with the age of the TV, what you would end up doing is buying parts from special electronics stores that came from a used TV that was taken apart. And who knows from there?

Ten years of ownership is good for a TV for the most part, some may last longer too, but in reality you may be better off just getting a new one rather than repairing it regulary.

Answer 3

I service all tvs for 31 years,,,the only way to accuratly check any coil or transformer windings is with a coil ringer...out of circuit. My Sencore ringer was $600.00. It accuratly counts the ring decay cycle on any coil, or wire. Ohm meters just check resistance..even a good coil would check falsely on just an ohmmeter., but would ring good on a ring test. Hope this helps clarify...

Answer 4

if it is clicking, its probably the flyback like you said. Ususally when the flyback goes out, the trippler goes out...or if one is dying, it'll drain the other. check that maybe?