Texas Instruments 990 Maintenance Manual page 28

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N
990
MAINTENANCE
UNIT
115 VAC,
s
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NGi.~- ~~~~ E
(B)133246A
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PROGRAMMER
PANEL
l/F BOARD
PROGRAMMER
PANEL
AC
POWER
CONVERTER
-,
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945128-1
CARD SLOT 1
990/4
MICROCOMPUTER
BOARD
WITH 4K
RAM MEMORY
AND LOADER
AND DIAGNOSTIC
ROMS
944910-3
MAIN
SUPPLY
STANDBY
SUPPLY
INTERCONNECT
WIRING IMPLEMENTED
USING ETCH
CIRCUIT BACKPLANE
AND SIX FULL-SIZE
BOARD CONNECTORS
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--,
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r--:i
1
:;--1
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UNDER
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TEST
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t6 1/0 TTL
MODULE
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'--------A'
L ____
::.J
1 /2 CARD SLOT 6
TTY/EIA
MODULE
945075-1
CARD SLOT 2
990/4
MEMORY
EXPANDER
BOARD
944935-10
(20K W/WRITE
PROTECT)
990/4 CHASSIS
---,
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_J
944960-1
990 POWER
SUPPLY TEST
SET
Figure 5-1. Model 990/4 Computer Hot Mock-Up System
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959371-1
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733 ASR DATA TERMINAL
945161-1
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_J
UNIT TEST
OF 990
POWER SUPPLY
BOARDS
HALF-SIZE
EXTENDER
BO/.RD
945071-1
FULL-SIZE
EXTENDER
BOARD
975170-1
COMBINATION
11JAL TRACE
81~~~~(.
MULTIMETER