MCR power supply in Discs of Tron - 5v too high

smalltownguy2

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I recently rebuilt an MCR power supply for a Discs of Tron environmental cab that I'm working on. The 12v adjustment dials in just fine, but I can't seem to back off the 5v adjustment - dialing back the pot brings the 5v to 5.4v under load, but that's too high. What should I do to be able to adjust this power supply properly?
 
I'm not sure what you can do to fix it other than a shotgun kit. However, if you're getting the proper +5v on the boardstack and the other boards that use it (flasher board, S&T and encoder board), you shouldn't have to worry about anything. They don't care what you get on the power supply as long as they their proper +5v.
 
I'm not sure what you can do to fix it other than a shotgun kit. However, if you're getting the proper +5v on the boardstack and the other boards that use it (flasher board, S&T and encoder board), you shouldn't have to worry about anything. They don't care what you get on the power supply as long as they their proper +5v.

Would a replacement pot remedy the situation?
 
If the pot is bad, replacing it might help. My TRON power supply has always given me just a little over +5v at the board, even with it cranked all the way up. But that's enough to keep the game running. Are your boards getting much over +5v? Is the game not working properly? Unless it's what you feel may be too high at the boards, I wouldn't worry about it.
 
You're getting both 5.4v on the power supply and 5.4v at all of the boards? That's a pretty efficient power supply and wiring! If the pot doesn't fix it, you might have to shotgun everything. Heck, you might do that (if you have it handy) just to save the time of going back and forth just in case. Plus doing it all at once may save you (or Vader) a headache down the road.
 
You're getting both 5.4v on the power supply and 5.4v at all of the boards? That's a pretty efficient power supply and wiring! If the pot doesn't fix it, you might have to shotgun everything. Heck, you might do that (if you have it handy) just to save the time of going back and forth just in case. Plus doing it all at once may save you (or Vader) a headache down the road.

The power supply board's been shotgunned already with a Bob Roberts kit. The only thing that wasn't replaced was the two board mounted IC's - an LM3900, and one smaller IC.
 
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