PDP-11 chassis and backplanes


model height power supply backplane usage
BA11-A 10.5 in H7140,
opt. H7750-B BBU
PDP-11/24, PDP-11/44, VAX-11/730
BA11-B PDP-11/35
BA11-C 10.5 in H720 PDP-11/20
BA11-D 10.5 in H750 PDP-11/05, PDP-11/10, PDP-11/35
BA11-E 10.5 in H720 PDP-11/05, PDP-11/20 expansion box, rack -ES, tabletop -EC
BA11-F 21 in two H742 or H7420 PDP-11/40, PDP-11/45, PDP-11/70, Unibus expansion - cards pull out left
BA11-G 7.5 in DDV11-E tabletop box w/ L-H Research power supply
BA11-J n/a n/a strong cover for table top PDP-11/05
BA11-K 10.5 in H765 PDP-11/05, PDP-11/34, PDP-11/35, Unibus expansion, MJ11, MK11
BA11-L 5.25 in H777 PDP-11/04, 11/24
BA11-P two H7420,
opt. H775 BBU
PDP-11/60, PDP-11/60 expansion box, 11D34
BA11-Y 10.5 in DYS50
BA11-Z VAX-11/730
BB11 four slot blank mounting panel (backplane w/ Unibus and power only)

Note that the H742/H7420 bulk power supply use up to five regulator assemblies (max four for the H7420-E and H7420-F) of various types, the H750 uses one regulator, and the H765 uses two regulators:

H744 +5V 25A
H745 -15V 10A
H746 +23.2V 1.6A, +19.7V 3.3A, -5V 1.6A used for MOS memory in 11/45
H754 +20V 8A, -5V 1-8A used for MF11-U/UP
H770 +15V 10A
H781 +5V 15-25A, +15V 4A H7440 with added +15V regulator and LTC output
H7440 +5V 25A
H7441 +5V 32A
H7850 +5V 2.5A, +12V 0.1A, -12V 0.15A used for MOS memory, supports H775 battery backup
70-14251 +5V, +12V, -12V

Unibus Backplanes

model organization
DD11-A four SPC, AB slots in middle for power (BA11-C)
DD11-B four SPC, AB slots in middle for two DF11
DD11-CF four SPC, power harness for BA11-F
DD11-CK, 54-11560 four SPC, power harness for BA11-K
DD11-DF nine SPC, power harness for BA11-F
DD11-DK, 54-11414, 70-11164-00 nine SPC, power harness for BA11-K
DD11-PK 70-11523 11/04, 11/34, 11/34a backplane
70-16905 PDP-11/24, M7133 KDF11-UA processor in slot 1
M7134 KT24 Unibus map in slot 2 CDEF (no grant)
extended Unibus in slots 2-6 AB
modified Unibus in slots 7-8 AB
Unibus in alot 9 AB
SPC in slots 3-6, 9 CDEF
NPR SPC in slots 7-8 CDEF (use G7273 grant in CD)
70-16502 PDP-11/44 KD11-Z processor
H9277-A, 54-15658, 70-20650-01 PDP-11/84
DH11-XX, 54-10333, 70-09561 DH11
MM11-S MM11-L
PCL11-BP, 70-07204, 76-06675-A PCL11-B
RH11-BP RH11


model height backplane organization power supply used in
BA11-M 3.5 in DDV11-A, H9270 4 Q18-Q18 H780 PDP-11/03
BA11-N 5.25 in H9273 9 Q18-CD H786, H7861 PDP-11/23
H9275 9 Q22-Q22 H786, H7861 PDP-11/23
BA11-R 5.25 in H9273 9 Q18-CD H786, H7861 PDP-11/23
BA11-S 5.25 in H9276 9 Q22-CD H7861 PDP-11/23+
BA11-U 15.75 in 3*H9270 PDP-11/03 in VAX-11/780
BA11-VA 3.6 in H9281-BA 2 Q18-Q18
BA11-VB 3.6 in H9281-AB 4 Q18-Q18
H9281-AC 6 Q18-Q18
H9281-QA 2 Q22-Q22
H9281-QB 4 Q22-Q22
H9281-QC 6 Q22-Q22
BA11-W 5.25 in PDP-11/23-AH
BA23 H9278 3 Q22-CD, 5 Q22-Q22 H7864, H7864-A MicroPDP-11
BA123 "world box" 70-22019-00 pwb,
54-17507-01 assy
4 Q22-CD, 8 Q22-Q22 H7260, H7261
DDV11-B 6 hex, ABCD are Q18-Q18
DDV11-CK, 54-13036 assy
VT103 54-14008 4 Q18-Q18 H7835

See Also

Last updated April 12, 2015

Copyright 2004, 2005, 2006, 2012, 2015 Eric Smith


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