Hi Tom Grok tells me: “ Yes, the DEC PDP-8/S uses many of the same flip chip PCBs as the original PDP-8 (Straight-8), particularly from the R-series Flip-Chip modules. Both models rely on these standard R-series modules as building blocks for their diode-transistor logic, though the PDP-8/S implements a serial architecture that reduces the overall number required. ”
You should be able to find the R series schematics on line. If not, contact me on Brendan at McNeill dot co dot NZ and I will share my PDF’s with you. I’m out of town for the next couple of days. Sent from my iPhone > On 17 Aug 2025, at 16:11, Tom Hunter via cctalk <[email protected]> wrote: > > I have recently bought a DEC PDP-8/s. It hasn't been powered on for about > 40 years before I got it. I cleaned it and did some repairs on it (glued > broken flip-chip handles, replaced all front panel lights, restored the > acrylic front panel to as new condition and built a new switch mode power > supply for +10V and -15V). > > After testing each flip-chip individually for dead shorts on the power > rails I reassembled the flip-chips into the backplane and on power up it > shows signs of life, but has a number of problems I will have to debug and > fix. > > Does anyone here have the original Engineering Drawings or good PDF scans > of the drawings? > > There are reduced copies of the PDP-8/s Engineering Drawings in Appendix A > of the two PDP-8/s Maintenance Manuals on Bitsavers, but I have not been > able to find scans of the actual Engineering Drawings. Some details in the > reduced copies in Appendix A are not legible. > > Thank you > Tom
