Arcade Power Supplies - What is the -5V terminal for?

[bperkins01]

Hi Everyone,

I have a PS showing up tomorrow - it has -5V and +5V  terminals (as well as 12v, etc)

+5V is what (I believe) is the most common.  I will be using it with an Ultimate I/O board.

What is the -5V terminal for?  I can't find any real references for it..
Just curious.
thx
Bob

[opt2not]

 Some older arcade pcbs use -5v  to function, and for audio circuitry.   Especially pre-JAMMA pcb’s.

[pbj]

Audio amps on the pcbs.

[bperkins01]

Thanks - I figured it was a legacy output.. Just didn't know what.

[harveybirdman]

Pro tip: If the sound isn't working or partially working on a board hook the -5v up before you go gorilla handed soldering in new components.

[yotsuya]

Pro tip: If the sound isn't working or partially working on a board hook the -5v up before you go gorilla handed soldering in new components.

Or selling them off on eBay because sound doesn’t work

[pbj]

Or giving someone negative feedback because they didn't know about it and thought the sound didn't work on the board you sold them.  (not that I'm still bitter about that 15 years later)

[Thenasty]

much better, post in the FREE section whoever wants to fix the sound issue.

[Vigo]

Pro tip: If the sound isn't working or partially working on a board hook the -5v up before you go gorilla handed soldering in new components.

Or selling them off on eBay because sound doesn’t work

Even better yet when the entire cabinet is sold for cheap because it is wired wrong.

[pbj]

Even better yet when the entire cabinet is sold for cheap because it is wired wrong.

Bought a Frogger once.  The guy that sold it to me dead owned dozens of games and didn't know that "FG" was the ground terminal on the power supply.  Fired right up 5 seconds after he delivered it.   

[Vigo]

Nice! 

Bout 6 months ago bought a mario bros for cheap because the owner couldn't get it to power on, plugged it in to power it up for years as he demonstrated to me, but it suddenly stopped working. I took it home, plugged it in, then flipped the switch and it worked right away. Best I can figure is the dude accidentally flipped off the power switch on the back that he never realized it had.

[pbj]

The ones I've seen nail a few sellers are the safety switches that were pressed in by the back door.  I guess someone loses the door, turns the switch downwards, and pulls it out to bypass the safety feature.  Works for years until they move it, and the spring loaded switch pulls back in.

Frankly, if it's not worth 15 minutes of their time to pull it out and look everything over, I'm not going to feel guilty about simple fixes.  I've been nailed plenty of times on bad boards and monitors.