Museum of the Game® & International Arcade Museum® Forums

I'm currently repairing a desert fox from 1972 and am having problems with the sound.
It uses something called the simulator system which is a set of PCBs with a transformer and one PCB looks like an amp.
I'm getting no sound at all-not even a speaker buzz.
Just wondering if anyone here has any experience of this sort of old sound system who could give me an idea on where to start.