Question about Toshiba 51H93 51" Rear Projection HDTV

1 Answer

Horizontal output transistor failure

The horizontal output transistor on my 51H93 TV has shorted several times, taking out the circuit fuse.

What could be causing this?

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  • JHD923 Apr 17, 2008

    Where could I obtain one of these mods?

  • JHD923 Apr 23, 2008

    Thanks, scott201201. Do you know of a third-party that would have information on these mods? I tried contacting Toshiba several times at several numbers, but they couldn't help me.

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1 Answer

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  • 170 Answers

Check b+ comming from p/s. also check for blue flat caps in line with h-output circuit. if blown out the side. remove them from circuit. also might have a HVT goin bad. I believe this is also the model that might have a mod for h-out running too hott that requires adding a resister in the h-drive circuit. also try a heavier duty h-output.

Posted on Apr 09, 2008

  • Scott Henderson
    Scott Henderson Apr 17, 2008

    i have only had to do one of them, but you can contact toshiba and talk to them, let them know that this is your problem and their tech know about it, and you would like the kit.

    or you can replace it with another h-output useing heat sync compound. but i would say use a stronger h-output.

    the right fix is the kit and i would ask to speak with tech support.

    if you can't get to them then ask for parts dept and have them look up your part number.

    good luck.

  • Scott Henderson
    Scott Henderson Apr 23, 2008

    http://www.tritronicsinc.com

    i think they have a kit for it, but to get the correct part number you may have to ask them. if they dont know get with me

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