Atari 800: Part 4
25A quick update. I got a request from Jeramy at @JVHShack for some measurements of the Atari 800 keyboard as he was designing a replacement using Cherry MX keys.
Whilst I had the machine apart I thought I'd quickly replace the 7805 and 7812 linear regulators with PSU3 versions from www.ezsbc.com.
Before the change the heatsink was hitting about 50°C, and the plastic on the top case about 40°C. After the change, well there is no heatsink to heat up 🤯 ... but there was still a small amount of heat felt on the plastic top case.
Of course, one source of heat will always be the rectification circuit, especially the diodes. And, of course, there's all the Modules installed including the CPU card.
However two large sources of waste heat have now been removed.
Part 1:
https://youtu.be/Bq564VngsNc
Part 2:
https://youtu.be/fIjrMqNlzCI
Part 3:
https://youtu.be/wgbqldsGHVo
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