So after 18 months of hibernation, I’ve decided the time has come to start building my replica PDP-9. As I’ve previously discussed this is going to be based around my original PDP-9 console and use the simh emulator to implement the CPU.
Peripheral wise, the machine will feature a non DEC paper tape drive together with a pair of TU55 drives which I ultimately hope to hook up to the emulator.
Ourwardly I aim to make the machine look as close to the original as possible although under the skin the truth will quickly become obvious.
The first step is build the racks. I’m intending to build these in timber to keep cost and weight down. To enable me to start planning the dimensions, I’ve extracted the following from various DEC documents which give some clues as to the dimensions (note all are in inches):




The plan is to build a twin rack frame as illustrated below so as to enable the paper tape and TU55s to be mounted:
