Upside down picture question

    This site uses cookies. By continuing to browse this site, you are agreeing to our Cookie Policy.

    • Upside down picture question

      Hey guys, I scored this machine yesterday. I know it's not exactly a super sought after game but it means alot to me!



      Anyway, my question-It's obviously a conversion because the harness is JAMMA which goes to an adapter then to the Sega 16 pcb. The ESWAT game looks and works just fine. But I tried to hook up X-Men and the picture was upside down and backwards. I researched that this is the yoke plug and if the vertical and horizontal yoke connections are individually flipped around this will correct the screen. My idea was to put each vertical and horizontal on switches so I can switch between the two "poles" whenever a new game is hooked up that requires it. Is this pretty common? Is it a bad idea? help please

      The monitor is a Phillips 19VKUP22
    • Messing around with monitors while running could put stress on the monitor board. Definitely don't mess with anything high voltage. If they were designed to have the polarity switched while running they would have a built in switch. I have seen these yoke swapper switch kits before, but I wouldn't trust it myself. I'm glad in your case it was a simple software fix.
      Woodies: Xevious, Millipede Cocktail, Pac-Man, Dig Dug, Donkey Kong, Joust Cocktail, Space Invaders, 3-KOAM Red Angle
      Candies: 3x Aero City, New Astro City, 2x Blast City, Net City, Crowin Case 203
      VAPS
    • KaPH33n wrote:

      Messing around with monitors while running could put stress on the monitor board. Definitely don't mess with anything high voltage. If they were designed to have the polarity switched while running they would have a built in switch. I have seen these yoke swapper switch kits before, but I wouldn't trust it myself. I'm glad in your case it was a simple software fix.
      Interesting. I didn't realize there were kits for this situation.

      Also, how high is the voltage going through the yolk connectors that I would theoretically switch?
    • nem wrote:

      Thousands of volts.

      I've had a horizontal yoke connector short and catch fire. It's not something I would play around with.

      EDIT: found the pic
      Yeah I actually ended up having to flip both horizintal and vertical yoke connectors on the board side (as opposed to the monitor side). It worked out fine. I first discharged the tube using the screwdriver method, while wearing rubber gloves for good measure. It worked out great. I am still curious as to why it was flipped to begin with. I even noticed that the stock eswat board had it's dip switch flipped to accommodate the upside down monitor.
    • brad808 wrote:

      thousands of v in deflection?!? Even horz should be less 200v, vertical less still.

      Just going on by what I've heard. It's still enough that I don't want to touch the poles on the yoke or remove the connectors when the monitor is on.

      EDIT: remembered this post by PrincessPrinPrin on AO:

      forum.arcadeotaku.com/viewtopic.php?p=481808#p481808

      The post was edited 1 time, last by nem ().

    • The problem is that deflection coils are an inductor. The electronics driving those inductors don't like it if they temporary disconnected and reconnected while running. You will end up with a defective chassis in no time. During the switch, the deflection will dissapear for a fraction of a second having your beam in the center of the screen. This can burn the phosfor of the tube in the center of it.

      You could get away with an automatic switch if it uses beefy relais and basically turns off the chassis, waits 10 seconds, switches the coils and turns the chassis back on again. It's the only safe method to do it but I wouldn't recommend it.
    • obcd wrote:

      The problem is that deflection coils are an inductor. The electronics driving those inductors don't like it if they temporary disconnected and reconnected while running. You will end up with a defective chassis in no time. During the switch, the deflection will dissapear for a fraction of a second having your beam in the center of the screen. This can burn the phosfor of the tube in the center of it.

      You could get away with an automatic switch if it uses beefy relais and basically turns off the chassis, waits 10 seconds, switches the coils and turns the chassis back on again. It's the only safe method to do it but I wouldn't recommend it.
      Yeah it really seems like a bad idea. Thanks for the help. I don't even really need to worry about that anymore as I manually flipped the connectors and everything seems to be good now.