Diagnosing ZX Spectrum RAM problems

In this video I'm demonstrating how I diagnosed RAM problems in two ZX Spectrums I bought on eBay. One Spectrum had a broken bit 6 in the lower RAM, the other a broken bit 2 in the upper RAM.

Just feeling the chips on the motherboard didn't show up anything as getting hot, and I didn't have any spare chips for the piggyback method.

I found DiagROM by Retroleum, which helped to identify the broken bits and repair both computers.

Here is the link: http://www.retroleum.co.uk/diagrom

Видео Diagnosing ZX Spectrum RAM problems канала Jens Christian Restemeier