800XL – initial list of problems

When I first looked over the 800XL, it clearly needed cleaning, but I wondered if the problems would all be cosmetic, or a little more involved than that.

Turns out it’s a bit more involved. The first issue was that the power supply wasn’t outputting any voltage. To overcome this, I found an old usb phone charger and soldered on the cable from the original power supply.

Original power supply lead soldered to usb phone charger

I hollowed out the old power supply brick with the idea that I will hide the new usb charger in the old retro case, but that’s for another day.

With a working power supply, next on the list was to power the machine on and tune the TV into the old RF signal from the machine.

I plugged it in, tuned in the TV and…

Not quite the output I’d hoped for…

…nothing. Well, not quite nothing, it was a perfect black screen, so there was at least a sign that something was happening.

Removing the motherboard, the RAM was found to be a make that is notorious for being temperamental (MT), with the exception of one chip that had clearly been replaced in the past.

7 dodgy make RAM chips and one replacement

I desoldered the old chips, fitted sockets and ordered some new old stock chips from eBay. Once they arrived, I plugged them in.

Then I powered the motherboard up to finally be presented with…

It’s green and blurry instead of blue and sharp, but it’s a picture!

A display! It was blurry and a funny colour, but it was a display.

Next up will be improving the display – there are a number of mods online to generate an s-video signal, so I’m going to try those and will document what I find to work.