Bally 6-digit displays... I'm working on Star Trek. I have one display with the same segment out across it. I replaced the appropriate MPS-A42 transistor (Q18), and also the decoder chip. The segment "f":
http://web.archive.org/web/20071019004706/www.pinrepair.com/bally/index3.htm#display
is still out.
The problem follows the display if I change it in another location, so its not the inputs. Its the display board.
One could argue that I replaced the bad transistor and decoder chip with defective parts, but not likely.
Any ideas?