configuration consists of the appropriate enclosure
TELEPHONE LINE STATION
and basic telephone set as shown in figure 6-2.
Bulkhead-mounted telephone sets, both water-
The telephone line station equipment consists of
tight and nonwatertight, are connected to the
a telephone set connected to a set of line terminals of
an automatic dial telephone switchboard and, in some
automatic dial telephone switchboard electrically by
cases, auxiliary equipment.
connecting the telephone line (ship's cable) to a
screw-type terminal board mounted within the
The auxiliary equipment consists of extension
enclosure. Desk-mounted telephone sets are
signal relays and extension signal devices (visual or
connected to the switchboard by an external connector
audible) for use in high-noise areas. An extension
block furnished with the sets.
signal relay is a relay in an enclosure mounted
externally to a telephone set. The operating coil of the
The handset holder and handset retaining
relay is connected in parallel with the ringer of the
mechanism are mounted on the front of the stainless-
telephone set. The relay contacts are designed to open
steel cover. The remainder of the components
and close a ship's 120-volt power circuit to energize
are mounted either directly on the back side of the
an extension signal. An extension signal is a visual or
cover or on a steel baseplate (chassis), which is
audible signal mounted externally to a telephone set.
The signal is controlled by an extension signal relay.
secured to the back side of the cover. There is a cutout
in the cover to allow the dial to protrude through
The telephone set is a compact unit that transmits
for dialing access. The cover can be mounted on
and receives speech, and signals the desired station.
any of the three enclosures. In addition, the set can
The telephone set is made up of a transmitter, receiver,
be flush-mounted in a console panel or bulkhead
dial, and ringer. The transmitter changes sounds into
current variations that are sent over an electrical
circuit. The receiver changes the current variations
back into sound. The dial, when operated, causes a
series of interruptions (impulses) in the current
flowing in the line circuit. The ringer provides an
audible signal when the station is called. The most
common telephone sets installed aboard ship today are
the type G sets.
There are two versions of the type G telephone set
available for use in the automatic dial telephone
system. Both versions are designed to provide
shipboard, point-to-point communications over
automatic dial telephone lines. Both versions can be
used for either one- or two-party service. However, the
physical makeup and circuitry of the two versions are
TYPE G TELEPHONE SET (VERSION 1)
There are four models of the type G (version 1)
telephone set: the basic nonrestricted set, the restricted
set, the portable set, and the modular set.
Basic Nonrestricted Set
The basic nonrestricted telephone set (fig. 6-1) is
designed for nonrestricted communications. This set
can be used in three different configurations to
Figure 6-1.--Type G (version 1) basic nonrestricted
accommodate all ships' mounting requirements. Each