Author Topic: REPAIR GUIDE - TurboExpress/PC Engine GT: Video Fix  (Read 8375 times)

RetroWeirdo

  • Newbie
  • *
  • Posts: 5
Re: REPAIR GUIDE - TurboExpress/PC Engine GT: Video Fix
« Reply #255 on: July 30, 2016, 04:50:08 AM »
I've seen something similar happen when the 1 10uf cap pads get ruined but not exactly the same. Also, are you by chance using a generic ac adapter? Does the same thing happen on batteries? I wonder if this is the sign of an actual bad screen.

The burn in on the screen is completely normal.

I will recheck the 10uf again. No I first tried this unit reassembled on batteries and noticed the problem, since then I have been trouble shooting it partially disassembled with power from a 1st party NEC TE AC adapter. That would kinda suck if the screen has a legit problem, Though it might be nice to upgrade to a newer LCD.

thesteve

  • Hero Member
  • *****
  • Posts: 2952
Re: REPAIR GUIDE - TurboExpress/PC Engine GT: Video Fix
« Reply #256 on: August 14, 2016, 10:02:30 AM »
Looks like something isn't getting the correct voltage. Make sure there are not any broken traces to any of the caps you installed.

I'm getting 7.8v from an AC adapter.
When unit powers on it drops to 3.8v
Checked some the caps, most read about 3.5-3.7v
Measured on pin 3 of the display ribbon cable only get -2.5v

Anything else I should check and where does the 24v start ?

Thanks

if your supply is dropping below 6V it wont work