Figure 6-29.--XY switch.

remote-control device. It may be operated by a

control of switching modules to seize and interconnect

dial or automatically pulsed from associated

ship lines and shore lines. The consoles are not much

control circuitry. A 100-point, two-motion switch

larger than standard type G telephone sets and can

can make electrical contact with any of 100 sets

be mounted on a desk or bulkhead, or flush-mounted

of contacts, taking two motions to accomplish

in a suitable panel.

the connection. With the switch mounted in a

horizontal plane, the switch carriage moves first

System Operation

in the X direction (left to right parallel to the

wire bank), and then in the Y direction (into the

This section explains the fundamentals of XY

wire bank). When mounted in the switchboard,

switching as used in the MDM 200/700 system. It also

the XY switch is located adjacent to a 42- by 10-

describes the operation of the rotary switch that is

wire matrix called a wire bank. This wire bank

used as a selector and the operation of the

runs the length of the switchboard and serves as

switchboard and control cabinets.

the contacts for the wipers of all the XY switches

in the system.

SWITCHING COMPONENTS AND LINE-

FINDING.-- The XY universal switch (fig. 6-29) is

THE XY SWITCH.-- The main components of the

the heart of the MDM system. It provides the means

XY switch (fig. 6-29) are an X-stepping magnet, a Y-

for establishing connections throughout the system.

stepping magnet, a release magnet, spring

The XY universal switch is a 100-point, two-motion,

Figure 6-29.--XY switch.

6-35