Friday, December 21, 2018

OH-180 (AKA converted VT103-AA)


This system has 2 MDB boards completely populate with 2732 eproms, presumably
the software for the system.

Digital-B2-VT103-AA-Oh180-Video-Terminal-3-1a-Amp-120v-ac
https://www.ebay.com/itm/292818958162

the VT103-AA is the system ID for a VT100 + Qbus but no tape drive

There is a  custom board in addition to MDB and DEC boards.

Some information

M8186  KDF11 processor
M8059FC  64Kx18    DLV1J-UG    chip Fairchild MB8264-150 (x18)  MB8264-15
M7941  LSI-11_Systems_Service_Manual page 288
M8043
MDB MLSI - MRV11-C  #400 40360 (16 x 2732) (x2)
-----------------------------------------------
Custom FTM-R1
Ser No 170
Chips: MC6850
J1 40 pin to M7941
J3 to external DB9F

74LS14
CD4047AE
74LS123N
SN74LS00

National 75453
National S8863N
SN74LS244N
AB 314E221331 (termination) (x2)
National DM74LS374
----------------------------------------------

EBAY listing photos.










Photos as received and examined



M8059FC

MDB MLSI - MRV11-C  #400 40360

Position of switches on custom board





MC 6850 data sheet MC6850.pdf 
National 75453 driver  DS75452n.pdf


Custom Board FTM-R1

DEC 7941 Parallel board


Full Rear View

Card Cage

--30--


Friday, September 21, 2018

Dec Unibus prototype boards, backplane and frame

There are two DEC PDP 11 unibus expansion boards, a dual block, and a frame to add it to a system.