How do i repair my tv screen

[chris khanje1]

I have a Singer tv screen. It started producing cracking sounds every time i switched it on in the morning. Eventually after a minute it stops and give display. One morning it did the same but never displayed. Now when i switch it on it shows the power light with the usual clicking sound but does not diplay. Anybody here who can help me please? I don't wanna take it to a technician in the presence of science forum

[Spyman]

I am no expert on TV screens but from the sounds I would guess there is a failure in the power supply.

 

A technician can probably repair it, but I would not advice you to fool around with it yourself as it has lethal electricity.

[Sensei]

I had exactly the same issue with mine LCD tv a few years ago. 1 month after end of warranty (not the first time I had such "accident", like in clock).

It turned out to be couple capacitors broken.

When I entered exact model name of mine TV in google as keyword, hundred threads about mine issue were the first one in search results..

Some people even took photos with arrows with comments "replace this, this and this". I have done so, components cost $2 or less, and TV is working fine for 6 years now.

After unscrewing it, capacitors were immediately visible bold.

Edited February 19, 2014 by Sensei

[StringJunky]

After unscrewing it, capacitors were immediately visible bold.

I'm not an electronics buff by any means but I know capacitors can be vary dangerous with charge in so I hope all knowledge and safety precautions will be acquired first before going near them in the TV.

[Phi for All]

I'm not an electronics buff by any means but I know capacitors can be vary dangerous with charge in so I hope all knowledge and safety precautions will be acquired first before going near them in the TV.

!

Moderator Note

Quoted for Truth. Please be careful with electricity.

 

We get too many people who join to ask questions like this and then never post again. We can only hope they're still alive.

[Greg H.]

If this is an old tube type display, then I will offer this warning:

 

DO NOT ATTEMPT TO WORK ON THE TV TUBE UNLESS YOU KNOW WHAT YOU ARE DOING AND HAVE THE PROPER EQUIPMENT.

 

These old tubes carry voltages in the thousands or tens of thousands of volts, and take special equipment to discharge safely. You can very easily kill yourself monkeying about in the rear of a tube style set.

 

Certain LCD sets can carry voltages just as high, so it's best not to DIY a television unless you have some idea what you're doing.

[StringJunky]

Might be a good idea to just have a general forum policy regarding modifying/repairing high voltage or gas equipment similar to that which already exists for medical matters or dangerous chemicals. The fact is if one has to ask how to fix this sort of equipment one doesn't understand how it works and hence prone to danger.

[Unity+]

I am beginning to worry as the OP has not posted in a while.

[Sensei]

I'm not an electronics buff by any means but I know capacitors can be vary dangerous with charge in so I hope all knowledge and safety precautions will be acquired first before going near them in the TV.

 

This is not exact description of mine tv model fix, but pretty similar:

http://blog.dr-ivan.com/2010/10/12/how-to-fix-your-lcd-monitor-changing-capacitors/

 

These capacitors have 1000 uF/25 V and 470 uF/25 V.

Edited February 20, 2014 by Sensei

[Externet]

Do you mean fix or do you mean symptom ?

 

That article on your link is good when that is the problem. You should visually inspect the electrolytic capacitors for bulging and with a continuity meter for short circuit across them even if not bulged.

When in need to replace, use good quality ones and if possible rated to a higher voltage that still fit their footprint.

Another mandatory test is to apply a flashlight directly contacting the screen and try to discern if there is a faint image but no backlight.

If there is an image, chances are the bakclight lamps, sort of tiny fluorescent tubes are worn out. Check also the electrolytic capacitors on the backlight inverter circuitry.

Try to locate the schematic diagram on the web if further difficulty to diagnose other stages, I may guide you up to a certain point depending on your skills.

[Spyman]

... I may guide you up to a certain point depending on your skills.

I was once told to never give advice to someone unskilled, because if you do and a fatal mistake is made with damage or injury as result, then at least a part of the responsibility for the accident rests on the "guide".

[Phi for All]

I was once told to never give advice to someone unskilled, because if you do and a fatal mistake is made with damage or injury as result, then at least a part of the responsibility for the accident rests on the "guide".

 

My father would never "give" anyone something that could obviously harm them. He charged me a penny for a pocketknife once, just so he could claim he didn't "give" it to me.

 

I think there's only one piece of advice you can give an unskilled person who wants to learn to do something dangerous: Find an expert and watch how they do it until the expert thinks you can do it alone. There are many people whose tombstones should read, "How dangerous can this really be?"

[Externet]

Thanks Spyman and Phi for all, I understand the concept, which could apply also for borrowing items, not only giving them.

 

For sure there is plenty of mutilated borrowers of chainsaws and buried car borrowers. The danger is in the unskilled person, not on the items.

That television is not a CRT type, works from mains mostly converted to 12, 5, 3.3 Volts. If the repairperson is not aware of dangers, should not drive on roads either, not because may kill himself, but kill us.