New project and a mistake in the beginning

I’ve got a new 8 bit computer sold as non working: The Atari 800XL

It has a few marks and scratches and little broken plastic but it’s overall condition is quite good. It needs a good clean though.

Since I don’t have any peripherals for the Atari line of computers I’ve ordered a power supply first. The thought behind was to see if I can get it working again an then buy some other stuff.
The power supply came quite fast but then the whole project slowed down and a few weeks had gone until I made my first observations and my first mistake.

After a visual inspection I plugged in the Atari and measured the voltage at a few points. I was surprised about the measurements and I couldn’t explain the readings. Unfortunately it was rather simple: The power supply has ground and +5V mixed. So hopefully I didn’t destroyed my new Atari completely. 😥
I’ve ordered a new power supply and a SIO2SD from Lotharek in hope that I’ll can fix it anyway.

Now I wait for the parts and hope that at least all custom chips are still working 😳

Got the new power supply and everything is working. I’m a tiny bit disappointed since I wanted to repair something but just a tiny bit 🙂
Now only the cleaning is left.