AT&T Bell System Plant Series Service Manual

BELL SYSTEM PRACTICES
Plant Series
SECTION 502-542-402
Issue 1, May 1970
AT&TCo Standard
SERVICE
1564HK AND 1564HL TELEPHONE SETS
1. GENERAL
1.01
This section is issued to provide maintenance
and connection information on the 1564HK
(MD) and 1564HL type telephone sets. The
connection information for these sets was formerly
contained in Section 502-525-425 which is hereby
canceled.
1.02
The 1564HK (MD) is replaced by the 1564HL
telephone set.
2.
MAINTENANCE
2.01
Maintenance of handsets, dials, and ringers
is outlined in sections covering these
components.
Removing and Replacing Housing
2.02
To remove housing, loosen captive screws
in base of set. Lift housing up and toward
front of set.
2.03
To replace housing, guide lower front of
housing over pushbuttons, align housing with
base of set, and gently press housing into place.
Tighten captive screws in base of set.
Lamps and Pushbuttons
2.04
Replace cracked pushbuttons or collars.
Remove accumulated dirt or film from lamps,
collars, and pushbuttons with a water dampened
cloth. Do Not Use Solvents of Any Kind. If
cleaning does not correct binding of pushbuttons,
replace button and collar assembly.
2.05
To replace defective lamp:
(1) Remove dial from mounting bracket.
(2) Lift lamp from socket with KS-6320 orange
stick.
(3) Align lamp contact surfaces when placing
new lamp in socket.
(4) Remount dial.
2.06
The button and collar assembly should be
carefully aligned to avoid interference with
removal or replacement of housing.
2.07
Poor key button illumination in 1564HK (MD)
telephone sets may be corrected as follows:
(a) If the station is terminated on a 66E-type
connecting block, loop-through straps can be
installed on clip terminals 5, 11, 17, 23, and 29.
Full pairs should be brought to the connecting·
block from the key system apparatus via inside
wiring cables.
(b) If station termination is made via A2:iB
connector cable or at a 3-way bridging
adapter, replace set with 1564HL or li)65HK
(MD) telephone set.
Mounting Cords
2.08
Mounting cords designed for use with 636A
key assemblies feature slotted wafer sections
for each line appearance (Fig. 1). This allows easy
arrangement of lines to pick-up buttons.
ft
No field maintenance should be
performed on the plug of plug-ended
mounting cords.
Loose Number Card Retainer
Note: Number card retainer P-25E803 has
replaced P-25E785, which has been rated
"Manufactures Limited."
2.09
If the number card retainer becomes so
loose on the faceplate that the number card
(c)
American Telephone and Telegraph Company, Hl70
Printed in U.S.A. Page 1