Sorry for bumping an old thread but there has been significant progress made in the DPB restoration.
Because it's the 40th anniversary of the DPB-7001. Having being previewed as a prototype in New York in 1981, at the beginning of the year i decided i should try and do something with it.
Right now the DPB can start from floppy, i can get into the painting functions and it appears now to be working ok, with a few caveats.
There is still a lot to do, i would like to make this into a system i can eventually take to retro computing shows and have people use it so it needs to be reliable.
I have released 4 videos so far on it, these are not a documentation of every step but more of periodic updates to the process as i went through and got it booting, links to them are below, there's also some screen captures of the video output. Remarkable quality output considering this was released in 1982!
I would like to say a big thank you to those that have helped so far
In summary there was a four major things wrong with it:
1: PSU Fault: No output from the original HiFlex PSU
Remedy: Replaced PSU with two Astec MP8 PSUs integrating them into the original PSU chassis.
2: Card Backplane / hiway mis-aligned: The previous owner had disassembled the entire machine but hadn't assembled the backplane correctly, many cards did not align with the sockets.
Remedy: Re-assemble, align backplane, clean all sockets and edge connectors
3: Incorrect Components: The previous owner had replaced several tantalum capacitors. Some of which were the wrong values which resulted in the CPU reset circuit holding the CPU in reset.
Remedy: Replaced with correct parts.
4: Bad EPROM: One eprom had gone bad and was touch / vibration sensitive.
Remedy: Replaced.
Now it seems i can boot the system i will be looking at the following issues that need to be resolved:
Replace the 8" floppy with something solid-state & backup all floppies.
Replace the 14" hard disk with something solid state
Replace various blown components on the video input/capture cards & test
The Videos:
Part 4:
Part 3:
Part 2:
Part 1: