Chuy i have a problem with this tv when i turn it on the tv seems turn it on but in 3 seconds seems turn it off and a relay sound is present and this happen about 3 or 4 times and then the sound of the relay turn it off and the tv stay in stand by and when i try turn it on again it don´t respond. the voltage in horizontal transistor is 136 volts in the momen that the tv turn on and then go to 88 volts when turn it off. please help me with this problem. thanks

The power supply is going in to protection. There is a short somewhere.

Since you sound like you are able to service the set, remove the CRT socket and see if the set starts up and has high voltage. If so, the CRT may have a short in the electron-gun, or it is being over-biased from the CRT board.

I don't know the particular model design of your set. In the models that I do know, I have had components on the CRT board go defective and cause over-biasing of the CRT and cause a shutdown on startup.

Sometimes the components on the CRT board fail because the CRT is at fault, and it is arching some very high voltage back out to the devices on the CRT board. In this case, they will soon fail again.

If the above does not work, then it is possible that the flyback transformer has some shorted turns, or there is a failure in the HV multiplier.

Other things that can cause a shut down is if there is any components in any of the areas of the set that are causing too much current pull from the supply.

These sets can become very involved and a challange for the most experienced of techs to service.


Jerry G.