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SECTION 5 1 8-450-1 00
CONTENTS
PAGE
Station Busy Console (6B 1 ) With MW
65
N. Station Restriction
70
0.
TOUCH-TONE® Dialing
70
5. GENERAL MAINTENANCE
79
570A KSU
79
EXTERNALLY MOUNTED UNITS
79
A. 33A Voice Coupler
79
B. 20A-49 Apparatus Unit
79
C. 22A-49 Apparatus Unit
79
D. Loudspeakers
79
KTUs
79
POWER UNIT
80
TELEPHONE SETS
80
TROUBLE ANALYSIS
80
6. DETAILED MAINTENANCE
80
LINE CIRCUITS (400-TYPE KTU)
8 1
CO/PBX LINE RINGING ARRANGEMENTS
8 1
POWER FAILURE TRANSFER CIRCUIT (452A
KTU)
. . . .
8 1
INTERCOM CIRCUITS
8 1
A . Selector Circuit (424B or C KTU)
82
B. TOUCH-TONE Adapter Circuit (440A
or 478B KTU)
C. Voice and Tone Alerting Circuit (456A
82
or B KTU)
. . . . .
82
D. 2-Path Access Circuit (460B KTU)
82
PAGING CIRCUIT (457C KTU)
82
Page 2
CONTENTS
PAGE
BACKGROUND MUSIC
82
MUSIC-ON-HOLD (45 1 A OR B KTU)
83
POWER DISTRIBUTION
83
1 . GENERAL
1 .0 1
This section contains identification, installation,
connection, operation, and maintenance
information for the 7A Communication System.
1 .02
This section is reissued to:
•
Rate the 832B, 2832B, 832C, and 2832C
telephone sets MD
•
Add information on the 832BM/2832BM,
832CM/2832CM, 832DM/2832DM, and 832EM/
2832EM telephone sets
•
Add information on the 575AM and 2575AM
telephone sets
•
Add information on the 400G, 451B, 456B,
460B, and 478B KTUs
•
Show the 440A KTU rated MD
•
Add information on the D-180656 kit of parts
for wall mounting of 832/2832 desk type
telephone sets
•
Change night transfer to ring transfer
•
Add information on connection of multiple
station-busy consoles
•
Clarify limitations on loudspeaker placement
•
Show new codes for keys in station-busy
consoles
•
Make corrections and additions to the
Ordering Guide
•
Revise and correct various tables and figures
•
Add new tables and figures
•
Revise text.