8-bit acorn hardware • Re: BBC Plug lopping

Two 560pF capacitors (in parallel) from a 240V 50Hz mains supply, should not leak more than 85µA combined.

Mark

I'm suspecting the Faraday shield on the switching transformer is the source of the leakage. It did surprise me somewhat that the Y capacitors weren't used to conduct this away, instead, the shield is connected directly to the incoming earth... I have to find a really bad BBC and then do some surgery on the PSU - it might be destructive, but at least I'd be able to count the windings on the transformer (I guess that is a plus)

Statistics: Posted by maniacminer — Thu Mar 27, 2025 12:42 am

---