The very next day I set about trying to fix the thing. Armed with the Atom Technical Manual, I was able to identify the chips that came with the basic Atom and I took out everything else. I then replaced every part I could with a spare. In the end I found it was the 6502 that was at fault. I was very fortunate to have a spare one and even more fortunate that it worked. The 6502 came in 1 Mhz, 2 MHz, 3 MHz and even 4 MHz speed versions so I knew that putting the wrong speed in could cause problems. The one I took out was a 6502-11 and one I put in is a 6502-13. I think this means I replaced a 1.1MHz version with a 1.3MHz one. Perhaps now I have a slightly nippy Atom!

The picture above shows the point after I got the Atom going for the first time.

For several minutes I ran round the house shouting "I've got an Atom!"

I later found that a couple of the RAM chips were broken as well and the Atom ceased to work if I plugged in all the video RAM. So, for the moment I am leaving the video RAM expansion out although I have put the Lower Text Space RAM back in. Thus I have a 7K Atom.

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