CatChat: DEC PDP-11

CatChat: DEC PDP-11

CatChat: DEC PDP-11
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PDP-11 Minicomputer
Contains a PDP-11/34, 2x RK05 DECPACK disk drives and a RK05j DECPACK disk drive.

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The best restoration resource is a series of 35 11/34 repair videos that Jerry Walker posted to YouTube.

Documentation can be found here: Index of /pdf/dec/pdp11/1134

There are two versions, the PDP-11/34 and the PDP-11/34a. The 11/34 uses M7265, M7266, and M8264 boards for the processor. The 11/34a uses M8265, and M8266 boards for the processor. The 11/34a supports the FP11 Floating Point processor (M8267), and KK11-A Cache Memory (M8268) options.

Since your machine has RK05 disk drives the 11/34 should have a 4-slot backplane containing the RK11-D disk controller (M7254, M7255, M7256, M7257).

You should make an inventory of all of the boards and what slots they are in. There are interrupt and bus grant wire-wrap jumpers on the backplane that are configured to accommodate the boards, so don’t put them back in the wrong slots.


It is very likely that I have the full field maintenance print set which includes the engineering drawings and maintenance manual. If you don’t have it and can’t find it on BitSavers or VCFed then I can loan it out. $1.50 per mont plus P&P :slight_smile: