Figure 6-1.--Type G (version 1) basic nonrestricted telephone set.

configuration consists of the appropriate enclosure

TELEPHONE LINE STATION

EQUIPMENT

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

cutout.

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

different.

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

telephone set.

accommodate all ships' mounting requirements. Each

6-2