Table 6-14--Maintenance Equipment

Table 6-14--Maintenance Equipment--Continued

EQUIPMENT

RECOMMENDED

APPLICATION

CATEGORY

TEST

ALTERNATE

EQUIPMENT

PARAMETERS

Removing

Scheduled

Sandpaper

corrosion.

Maintenance

No. 000

Removing

Scheduled

Cotton Cloth

dust and

Maintenance

dirt parts.

Disconnec-

Corrective

Soldering Iron

ting wires.

Maintenance

Connections between other pairs of telephones are

DIMENSION 2000

made over the common path in a similar manner, with

The Dimension 2000 PBX is a time-division

each connection using time-division (microseconds)

switching system. It is designed to give up to 2000

instants for switch closure that differs from that of any

lines and 353 trunks. Solid-state technology makes

other connection.

possible the use of time-division switching and stored

The primary switching system consists of four

program control. The stored program contains a wide

basic cabinets. These are the common control cabinet,

variety of available features. Self-diagnostic mainte-

the module control cabinet, the line cabinet, and the

nance routines reduce the time required to maintain

auxiliary cabinet. The common control cabinet houses

the system. These features and routines are program-

the processors, memories, and control equipment. The

med on the system's memory tape. Features are added

module control cabinet contains the network control

or modified by input to the memory tape and the

circuits, trunk circuits, and line circuits. Additional

necessary hardware to make the feature work.

line circuits are contained in the line and auxiliary

cabinets.

The system has a battery pack for a backup power

supply. It is capable of supplying the system for a

Attendant's Console

minimum of 2 hours.

The attendant's console is a desktop piece of

Switching System

equipment from which the attendant handles

assistance calls. Keys are provided for each of the

Time-division switching is the name given to a

control functions. All calls made by the attendant to

new approach whereby calls travel over the same path

trunk lines or station lines are made using touch-tone

but are separated from each other in time.

dialing or the attendant direct station selection and

In this method the caller and the called party's

trunk group selection feature.

telephone is connected to a common path by a transis-

The console is fully electronic. It is equipped with

torized switch that opens and closes synchronously at

light emitting diode indicators, nonlocking push-

a rapid rate, During the brief closures, 1 microsecond

button control keys, audible ring indicator with

out of every 100 microseconds, a series of pulses is

volume control, and touch-tone telephone pad for dial-

transmitted from the sending connection.

up telephone service.

Each pulse represents a portion of an electric wave

from the calling party's telephone. The electric wave

Maintenance

is reconstructed by the means of a filter, placed

The Dimension 2000 PBX circuits are replaceable

between the switch and the called party's telephone,

circuit cards. The circuit card components are not

which converts into a replica of the voice sound

intended to be replaced in the field. The system is

originated by the calling party.

6-70