Bingo:General disclaimer
Standard Disclaimer
Bally stopped making these machines around 1980 and sold all the stuff to companies in Belgium. At around that time, the games switched to solid state.
That means there's no factory support, no factory training, and no factory experts. There are, however, a few people floating around who have picked these games apart and mostly figured them out. Having lost their sanity in the process, they have shown a willingness to help other people deal with their machines.
However, nobody is taking any responsibility for the information posted on this site, or the repercussions of following any advice you may receive. For example, if you touch a 120V circuit while standing on a cat to see a mixer rotor from a higher angle and the cat gets zapped, sorry, but we can't be sued.