Section III. MAINTENANCE PROCEDURES

TM 11-5805-387-34-2

Section III. MAINTENANCE PROCEDURES

2-8. REMOVING AND REPLACING MODULES

DEATH ON CONTACT may result from contact with high voltage in modem modules. Scope

module A2 contains 1,100 volts dc; loop battery in module A5 contains 127 volts dc. Set ON/OFF

switch on the front panel to OFF before attempting any removal procedures.

CAUTION

Be careful during removal and replacement. You can prevent accidental damage to other parts,

and can prevent potential short circuits caused by dropped hardware. When removing and

replacing a part, check carefully for loose hardware or insecure electrical connections. Do not

operate the equipment until you make these checks.

NOTE

The procedures below are for modules A1, A2, A3, A4 and A5. The procedure for scope module

A2 is listed separately in this paragraph.

REMOVING MODEM CHASSIS FROM CASE

Loosen six captive screws around outside edge of front panel.

Grasp ribbed frame around outside edge of front panel.

Carefully pull modem chassis out of the case.

RECEIVE AUDIO, TRANSMITTER, RECEIVER, LOOP BATTERY MODULES

REMOVE

Remove modem chassis from case.

Loosen the four captive screws holding module to chassis.

Pull up on bail handles to unplug module from chassis connector.

Lift out module.

To remove module dust cover, turn bail handles approximately 900 counterclockwise until they release.

Lift off cover.

REPLACE

Replace dust cover: Place cover over module; press down bail handles and turn approximately 900

clockwise until they lock in place.

Plug new module into chassis connector.

Tighten the four captive screws to secure module to the chassis.

Replace modem chassis in case.

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