(Topic ID: 260467)

Stern star trek, gate coils

By isJ

4 years ago



Topic Stats

  • 7 posts
  • 2 Pinsiders participating
  • Latest reply 4 years ago by isJ
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    #1 4 years ago

    Hey folks! Hoping someone with a bit more knowledge can help me out here. Both of my gates on my stern star trek in the back burnt out. I replaced both and they were working initially, however the right stayed engaged and started smoking after about five seconds.

    Turned off game and measured voltage at connectors to both gates, both have 75v running to the coil. I assume these should be 50v?

    Visually inspected at Q51 and 52, seem fine. Checked ground and 50v, getting 75v as well. Does this mean my BRDG1 is shot and should be replaced?

    #2 4 years ago

    Also measured at the 50v fuses, both were at 75v.

    #3 4 years ago

    Welp I am stupid. Measured on TWD and those measure 75 as well.

    #4 4 years ago

    Looking at F7 and F8, when the door is open, the LEDs slowly discharge instead of turning off immediately.

    #5 4 years ago

    The voltage is fine. If they’re burning out, likely the transistor that controls them is shorted to ground. Star Trek uses FETs which test different than darlington.

    Do not replace the coils until you confirm the shorted FETs; you’ll keep melting coils.

    #6 4 years ago

    You cannot visually inspect a transistor unless it’s blown out, which they don’t need to be visually blown to be shorted.

    You’ll need a meter to check the FET.

    #7 4 years ago

    Ty very much!

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