PDP 11/73 (x2)

Acquired two of these, which seem compete.

Pulls from some time ago badged for system which they were embedded in.

They appear to contain a DMA channel of some sort, but otherwise have hard disk and floppies.

Preliminary survey of boards:

Rear view of one system (top) front of other.  Floppy drive is missing flap on one system

Inventory (Top to bottom)
*1
M8190-AB  (quad)

M8190-AB    KDJ11-BB    Q   J11 CPU 15MHz with 2 boot & diagnostic ROMs

M8190-AB                    FPJ11 compatibility (warm floating point, but

M8190-AB                    will accept FPA)

M8190-AB        Refs: EK-KDJ1B-UG, uNOTE N#039

*2

M8067-LF   (quad)

M8067-LA    MSV11-PL    Q   512-Kbyte MOS memory with parity CSR

M8067-LA                    (Also M8067-LC, -LF, -LH, -LJ, -LP, -LV)

*3

M3104  (quad)

M3104       DHV11-A     Q   8-line Asynchronous Multiplexor, with DMA

M3104           Refs: EK-DHV11-TM, EK-DHV11-MC, MP-01783, ZJ362-RZ

M3104           Refs: uNOTE N#041

*4

M7651  (dual)   M9047  (dual)

M7651       DRV11-WA    Q   18/22-bit DMA general purpose parallel interface

M7651           Refs: EK-DRVWA-UG, MP-01582, ZJ244-RZ, uNOTE N#041

M9047                   Q   Grant continuity (also M9047-SA, -SF)

*5

M8639-YB  (quad)

M8639-YB    RQDX2       Q   RD51/52 & RX50 MFM Disk control module, can

M8639-YB                    be expanded  (must be final DMA device in bus)

M8639-YB        Refs: EK-RQDX2-UG, MP-01731, uNOTE N#043

(*n) indicates quad slot# from top

DMA channel and grant card nestled in the bus.

Front Panel

System contains an RZ disk, as well as dual floppies.