2 ms·

Yeah an 11/70 needs 3-phase which I don't have.

• adrian_b 4y ago
  It is more important if you have enough electrical power available. Building or buying a 3-phase inverter or a power supply unit that could replace the original power supply are much easier tasks than building the logic boards of PDP-11/70, which you have. If the power requirements exceed what is available at your location, you could still make the PDP-11/70 work for very short times, by using a large enough UPS with a 3-phase inverter or with a substitute power supply, and charging the UPS, then starting the PDP-11/70 with the UPS disconnected from mains. The power requirements can be reduced a lot in comparison with a real PDP-11/70 if only the processor boards are used and the memory boards are replaced by a modern FPGA board implementing the protocol of the DEC memory bus. The maximum size of the PDP-11 memory (4 MB) is small enough that it can be implemented with the internal SRAM of many FPGA chips, no external DRAM memory is needed.
  • dboreham 4y ago
    > It is more important if you have enough electrical power available. I have 7.5KV in my yard so absolute power is not a problem. Good point about emulating memory and thereby getting away with a smaller PSU. Also need to emulate a disk drive. I have controllers for various drives but no physical drives (those are tricky to get working today even if they can be tracked down due to degradation of materials).