The whole battery mounting board is shot – entire traces corroded on it, and the contacts have effectively dissolved.
Fortunately, the machine was designed in 1977(ish) and batteries have gotten a lot better since. 6x AA batteries can now be replaced by a single modern 9V and it’ll deliver enough current. So I’ll mount a new 9V holder and solder it into the battery board wiring harness. I’ve already tested that solution on the breadboard and the machine appears to work.
The whole battery mounting board is shot – entire traces corroded on it, and the contacts have effectively dissolved.
Fortunately, the machine was designed in 1977(ish) and batteries have gotten a lot better since. 6x AA batteries can now be replaced by a single modern 9V and it’ll deliver enough current. So I’ll mount a new 9V holder and solder it into the battery board wiring harness. I’ve already tested that solution on the breadboard and the machine appears to work.
9V batteries existed in the seventies. They just have far less capacity than six AA cells.
I agree. However the Ah capacity of a modern 9V is pretty good compared to the 70s. Unless you buy the cheapest 9V crap you can find ;)