The Beginning

By Anonymous -
Hi! My name is Dawson and this blog will be documenting the restoration process of a DEC PDP-12. As stated in the "About" section, this machine has sat untouched for a long time and appears to be in very good condition. This is PDP-12 #435. We initially assumed that because it been sitting untouched for so long, it would still be in one piece and everything would be there. Well... that turns out not to be the case.

Upon further inspection it appears that at some point in this machines life someone took one of the 4k core stacks of memory. The machine appears to have originally configured to run with 8k, meaning it should have come with 8k from the factory. Nothing else appears to be missing yet that we know of. A more detailed inspection of the installed Flip Chips and other components will happen soon.

Along with the computer we received many of the original manuals and tapes. I will put these in another blog post for ease of reference.

Upcoming on the restoration agenda:
  • Get the power supply working
    • Reform the capacitors and make sure the outputs are within the original tolerance ratings
  • Clean everything
    •  Clean the cabinet, clean connections, and document what Flip Chips we have and what analog devices or other peripherals are connected
  • Replace the 220V/30A plug with a "normal" plug for a 120V outlet







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