I once supervised a student who had a holiday job at Sinclair. He told me about their quality control methods. They were contract manufactured, so as soon as they came from the manufacturer Sinclair sold them without any further testing. If they were returned as non-working they sent the customer a 'new' one and placed the returned one in the service department. The service department's policy was that most problems were simply users not knowing how to operate them, so they opened it up, painted a white dot on the PCB, put it back together and put it in the 'new' stock to be sold again. If, when they opened it up it already had a white dot on the PCB they painted on a second white dot, closed it up and put it in the new stock. If it had two white dots they put it in the waste bin.
I once supervised a student who had a holiday job at Sinclair. He told me about their quality control methods. They were contract manufactured, so as soon as they came from the manufacturer Sinclair sold them without any further testing. If they were returned as non-working they sent the customer a 'new' one and placed the returned one in the service department. The service department's policy was that most problems were simply users not knowing how to operate them, so they opened it up, painted a white dot on the PCB, put it back together and put it in the 'new' stock to be sold again. If, when they opened it up it already had a white dot on the PCB they painted on a second white dot, closed it up and put it in the new stock. If it had two white dots they put it in the waste bin.
Oh wow that’s mad
Jam in new ceramic caps. And a TSR-1 2450.
I might just try that. I do have some switching 5v regs but didn’t bother as I couldn’t get it working🙄