When I was a newly qualified electronics engineer (many moons ago) in Brisbane I was asked to a meeting at a very large amusement company that operated jukeboxes, pool tables and EM pins in about 30% of the pubs and clubs in the Brisbane area. They had just received their first electronic pin, a Bally Playboy. The techs there were way out of their depth when they opened the backbox and looked, mostly being ex-telecom techs. PCBs were a complete mystery to them as was electronics in general.

I knew one of the techs socially and he asked me to come and look. When I looked I could see straight away things like coil driver transistors etc and when I could actually 'read' the circuit diagram they were all stunned. The boss asked me "when could I start work there". That was my entry to the "amusement" industry, I started the following week.

I relate this story because when the owner of this company ordered his first batch of Bally electronic pins he also ordered a "Bally factory test bench". This was basically a wiring harness connected to all the boards and a power supply and a massive array of lamps, switches and displays all mounted in a very large fold-up cabinet.

You would plug in the board you suspected of being faulty and could work on it more easily than in a machine. It was hardly an earth shattering machine. I know that quite a few of the larger operators bought these at HUGE cost because they were very worried that their non-electronic techs (which was probably 95%) needed every bit of help they could get to keep these new machines working.

Mostly we never needed the test machine but it was handy to soak test boards or used if a tech brought suspect boards back from the field.

The bottom line is that there are many of these test benchs out there, or at least there were, most were probably stripped for the boards. They are certainly not exclusive to a particular Bally agent at all despite what he might claim. Their value is dubious in my mind as it really just replicates a pinball machine - it doesn't 'test' anything that you cannot just as easily test with the board in your machine. These days you don't have the issue of the pin being in a corner store when it made sense to bring the offending boards back to the workshop where the test bench was used.