I have a Bally Whodunnit and I have been trying to debug a flasher issue. First of all, the machine has a rottendog driver board. So here is a description of the problem.
The flashers for the game are both on the playfield and in the backbox. The flashers are connected through J125 (the backbox) and J126 (the playfield). When a bulb is in both the backbox and the playfield, for some reason they stay on (LIT UP). If I pull out the backbox bulb, the playfield light goes off but flashes properly when fired. I thought that the transistors might be worn out, so I have replace two of them and it has not resolved the issue.
I am about to try to replace Q3 which reads from the bus and triggers the driver transistors, but I am not convinced it is damaged since they work properly when a bulb is in but not when two are in.
Anyone ever experienced anything like this? I am completely stumped!
The flashers for the game are both on the playfield and in the backbox. The flashers are connected through J125 (the backbox) and J126 (the playfield). When a bulb is in both the backbox and the playfield, for some reason they stay on (LIT UP). If I pull out the backbox bulb, the playfield light goes off but flashes properly when fired. I thought that the transistors might be worn out, so I have replace two of them and it has not resolved the issue.
I am about to try to replace Q3 which reads from the bus and triggers the driver transistors, but I am not convinced it is damaged since they work properly when a bulb is in but not when two are in.
Anyone ever experienced anything like this? I am completely stumped!