Bally Midway Up N Down

[jonhughes]

I got this PCB about 2 years ago, allegedly fully working from the U.S. off EBay. Once the PCB arrived it had graphic issues and no sound.

The graphic issues were cleared up by patching a broken trace but the sound fault was a mystery.

Without schematics I had basically lost enthusiasm for it, even though I really wanted it working.

I decided recently again to search for the schematics but was out of luck again. The PCB manual does contain the board schematics but no one has scanned them on line. The internet search did lead me to an EBay listing though - this one in fact:

http://www.ebay.co.uk/itm/Upn-Down-Up-Bally-Midway-Sega-Original-Manual-Schematics-Arcade-USED/282660691822?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

As luck would have it they have photographed the schematics of the sound section for display purposes, ta very much.

Although the schematics didn't give me the faulty component they did allow me to eliminate a load of other things. Fault turned out to be a bipolar transistor array (ULN2003A) at IC55 changed and socketed.

Up n Down was a fav. of mine and very happy to have this one fully working.

 

[Eddhorse]

Good work, impossible without the schematic I'd say.

Is there a place to upload schematics for everyones use?

Will check out the game later today

 

[jonhughes]

Looking at the board the component was on the other side of the PCB from the sound section.

The chip gives signals to a D8255A - IC21 (40 pin DIP) next to the right dipswitch.

jonhughes2017-10-09 10:30:16

 

[Hurray Banana]

Great work as usual John