AT&T Bell System G6 Series Maintenance Manual

BEll SYSTEM PRACTICES
AT&TCo Standard
SECTION 501-211-102
Issue 6, May 1982
G6-, G7-, GS-, G13-, G66-, AND K6-TYPE HANDSETS (AMPLIFIER)
IDENTIFICATION, CONNECTIONS, CONVERSION, AND MAINTENANCE
1. GENERAL
1.01
This section contains information for G- and
K-type amplifier handsets. Also information
on D-180413 (modified GS-type) handset is included.
These handsets are intended to replace standard G-
or K-type handsets for use by persons with impaired
hearing or weak speech and for noisy locations.
1.02
The reasons for reissuing this section are
listed below. Revision arrows are used to em-
phasize the more significant changes.
• Add G13D-104
• Add G66AM-type handsets
• Add K6C handset.
1.03
Table A lists these handsets and their compo-
nent parts.
2. IDENTIFICATION
A. G6-Type {Impaired Hearing)
2.01
The G6-type handset is equipped with an in-
ternal receiver amplifier unit. The volume
control potentiometer in the center of the handle ad-
justs the loudness setting of the receiver so the hand-
set may be used by persons with normal hearing as
well as persons with impaired hearing.
2.02
The G6B (MD) handset assembly has two
transistorized amplifiers and will operate on
either polarity. The units are located on a printed cir-
cuit board in the receiver cavity. The amplifier, po-
tentiometer assembly, and handset cord connect to a
terminal board located in the transmitter cavity.
2.03
Three versions of G6B (MD) handsets have
been produced and are referenced as early
(before 1974), later (1974-1977), and last (1977-
1979). The last version can be identified by a black
plastic plate around the volume control assembly in-
stead of the chrome metal plate on previous versions.
The receiver amplifier board on the last version has
three screw terminals. In the G6B last version, the
yellow conductor in the handset cord is removed. This
is a normal condition since the yellow lead is not
used.
2.04
The G6BM handset is identical to the G6B
(MD) last version handset except that it is
equipped with a jack to receive the plug-ended H4DU
handset cord which must be ordered separately.
B. G7-Type (Weak Speech)
2.05
The G7-type handsets are equipped with an
internal transistorized transmitter amplifier
intended for use by persons with weak speech. The
potentiometer in the handle controls the level of the
transmitter output. The transistorized transmitter
amplifier is located on a printed circuit board at the
receiver end of the handle. The polarity guard and
one inductor are on a terminal board in the transmit-
ter cavity. The potentiometer assembly, amplifier,
and handset cord connect to a terminal board in the
transmitter cavity. Internal connections are made by
spade-tipped leads.
2.06
The G7BM handset is identical to the G7B
(MD) handset except that it is equipped with
a jack to receive the plug-ended H4DU handset cord
which must be ordered separately.
C. G8-Type (Noisy Locations)
2.07
The GS-type handset is equipped with a tran-
sistorized receiver amplifier, a volume control
potentiometer, and a push-to-listen switch and is in-
tended for use in noisy locations. The volume control
provides up to 10 db of additional receive gain. The
push-to-listen switch, when operated, decreases the
transmitter output and increases the gain of the re-
ceiver amplifier.
2.08
Two versions of GSB (MD) handsets have been
produced and are referenced as early (before
NOTICE
Not for use or disclosure outside the
Bell System except under written agreement
Printed in U.S.A.
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