I worked in the arcade industry in the late 70's and early 80's. I was trained on EM Pinball, Jukebox and Pool Table repairs. I was lucky enough to be working in the industry as the first electronic pinballs and arcade games come out (Golden Age).
After a long time away I am getting back into repairs and have been gathering up test equipment that was a luxury or did not exist back in the day. I have also been using my electronics engineering skills to make up some tools/accessories.
Currently I have made several microprocessor NOP modules that support troubleshooting and signature analysis and also protection modules for the fluke microprocessor troubleshooter pods.