John's Arcade Forum - Classic Arcade and Pinball Collecting and Restoring Discussion Forum - RETRO MAME - Nintendo Vs Forum

Hey guys I was watching johns final journey video and he was checking voltage and it said 5.157.  Now our "tech" at my buddies vending company says when you set voltage to set it at 5.15.  is that wrong?  should I be setting it at 5 even?

I would try to get it as close to five volts as possible, closer to five would be best. If you can get a reliable five volts constantly then that's perfect. So yes try to have five volts even, as you could overtime overload chips and circuits. Generally though there is a tolerance of so much. I'm not sure about arcade boards but PC's usually are right on the volts that they need, or stuff doesn't work.

Keep in mine that when I was checking it, it wasn't under load. The PCB wasn't plugged in. In previous videos I was testing it at the PCB and that 5.15 was closer to 5.0v when the PCB was plugged in. The 5.157 didn't have me worried as I knew there would be voltage drop under load and by the time it reached the PCB. It felt "safe" to me and confirmed my voltage knob didn't move while the power supply was out of the game and since the last time I properly adjusted it in the game.

yup .. when you check voltage at the power supply with no load (machine off, boards not connected)  its diff from when you check it at the edge connector while the game is operating (under load)