Figure 5-19.--Plotters transfer switchboard.

Figure 5-19.--Plotters transfer switchboard.

lever-operated spring return or spring return rotary

circuit 81JS. Any of the remaining jackboxes, JS3

through JS10, may be connected to one of the five

switches are provided at all calling stations. Buzzers,

sound-powered circuits by simply closing the associated

horns, bells, and drop-type annunciators are installed at

switch.

the associated called stations. Buzzers are used in low

noise level spaces. Horns are used in high noise level

CALL AND SIGNAL

spaces, and bells are used in other spaces. Annunciators

CIRCUITS

are provided at all stations where two or more similar

audible signals are required.

Call and signal circuits used in conjunction with a

ship's sound-powered telephone system provide the

To use the circuit, the caller operates a switch at the

means of calling and signaling between stations of the

calling station, which in turn energizes the audible

various sound-powered telephone circuits. The call and

and/or visual signal devices located at the called

signal circuits are designated E, EM, and MJ.

station.

CIRCUIT E - SOUND-POWERED

Circuit E is divided into the following functional

TELEPHONE CALL

circuits:

CIRCUIT

1E-Cruising and miscellaneous

Circuit E provides a means of signaling between

2E--Ship control

sound-powered telephone stations, where not more than

six stations are to be called by the calling station. The

3E--Engineering

circuit operates on 120-volt, 60-Hz, single-phase power,

4E--Aircraft control

which is usually supplied by the main IC switchboard.

Watertight and nonwatertight push buttons and

5E--Weapons control