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Horizontal output transistor

My television has two circuit boards a main board located on the floor of the set and a secondary board located on the crt tube on which board will I find the horizontal output transistor... I have another television can I simply swap them if they are the same

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  • gottaproblem
    gottaproblem Feb 12, 2008

    Think I have located the horizontal output transistor pretty much thank you, will try swapping them, both televisions are going to the tip now so if it saves one of them, then all well and good... on top of the tube is a large rubber cup that has come loose does this make a difference to anything

  • ktibug Sep 17, 2008

    my rca tv will turn off then try to turn on three times. i have the back panel removed and there is a burning smell.

  • Anonymous Mar 29, 2014

    Output transistor for Diamond 54cm colour TV



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You can Swap them if they are of the same rating, must check the wattage. cause the width problem & the power transistor become over heat. you can also use both of them in parallel, if they are ok. your tv live longer.....

Posted on Feb 12, 2008

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Most likely the transistor will be on the main board. It will also be mounted to a heatsink. The board you see mounted to the rear of the CRT is not associated with the horizontal and high voltage. Follow the high voltage wire attatched to the side of the CRT back to the flyback transformer. You should find the transistor near the transformer.

As for swapping them out: you can swap them out if both TV's are the same model number or if the transistors have the same part number. If not, I would not do it. You have to make sure that the specifications of the parts are identical otherwise you can damage the replacement part and possibly the TV.

Let me know if I can be of further assistance to you.

Good luck!
- Jim

Posted on Feb 12, 2008

    SHARCNET-USA Feb 12, 2008

    The rubber cup supplies the high voltage to the CRT. The cup will move around a little but it should not be loose. Make sure you let the TV set bleed off the high voltage before you touch this connection. The correct way to discharge this lead is to attach a lead to the chassis ground and the other end to a screwdriver and insert the screwdriver under the rubber cup and touch the metal lead under the rubber cup. Make sure your hand is insulated when doing this. You can remove the rubber cup by grabbing the rubber boot and squeezing it. This compresses the clip under the boot and allows you to remove the lead from the CRT. make sure you do this with the set unlugged and with the CRT anode fully discharged.

    Make sure that both horizontal output transistors are the same part number.

    Good luck, please let me know what happened.

    - Jim



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