Section II. INSTALLATION

TM 11-6625-542-14-1

table

2-2. Unpacking and Checking

1-1. Report all discrepancies in accordance with

a. Step-by-Step Instructions for Unpacking

paragraph 1-3. Shortage of a minor assembly or part

Shipments (fig. 2-1).

that does not affect proper functioning of the equipment

(1) Place carton on a table or workbench.

should not prevent use of the equipment.

(2) Open outer corrugated carton, moisture-

(3)

If the equipment has been used or

vaporproof barrier, and remove silica-gel bags.

reconditioned, see whether it has been changed by a

(3) Remove intermediate corrugated carton.

modification work order (MWO). If the equipment has

(4) Open intermediate carton and remove four

been modified, the MWO number will appear on the front

polystyrofoam corners.

panel near the nomenclature plate. If modified, see that

(5) Remove inner carton.

any operational instruction changes resulting from the

(6) Open inner carton and remove wadding,

modification have been entered in the equipment

corrugated pads and spare parts carton.

manual.

(7) Lift AN/USM-108A from inner carton.

NOTE

b. Checking Unpacked Equipment.

(1) Inspect the equipment for damage incurred

Current MWO's applicable to the equipment are

during shipment. If the equipment has been damaged,

listed in DA Pam 310-7.

report the damage on DD form 6.

c. Cleaning New Equipment. After the equipment

(2) See that the equipment is complete as

has been thoroughly checked, clean all items with a soft

listed on the packing slip. If a packing slip is not

cloth.

available, check the equipment against the data listed in

Section II. INSTALLATION

back of the case, the equipment is wired for operation

2-3. Cable Connections

from an ac power source of 117 volts (range 105 to 125

The following steps outline the cable connections to the

volts) at a frequency of 50 to 60 Hertz. If operation from

AN/USM-108A.

a 234 volt source (range 210 to 250 volts) is required,

a. Place Connector Adapter U-287/U into correct

follow the procedures outlined below (fig. 2-2):

power source and attach green grounding terminal to

a. Remove the left side panel of the instrument.

ground.

b. Remove jumpers between terminals 1 and 2

NOTE

and terminals 3 and 4 of T101. Connect jumper across

Step a above is not necessary if grounding

terminals 2 and 3. This arrangement places the two

provisions are already at the power source.

primary windings of the power transformer T101 in series

b. Connect Electrical Power Cable Assembly CX-

for operation on 234 volts input.

10631/U to rear of AN/USM-108A and power source.

c. Remove jumpers (1 and 2) at terminal strip for

c. Attach RF Cable Assemblies CC-2634/U to

crystal oven transformer T102. Connect jumper (3) as

TRIGGER OUT and MARKER OUT connector on front

shown. This arrangement equips transformer T102

panel.

operation on 234 volts.

NOTE

CAUTION

Electrical Lead Assembly CX-4809/U may be

Always change the connections on the crystal

used in place of either radiofrequency cables

oven transformer when changing connections

depending on application.

on the power transformer.

2-4. Power Connections

Unless otherwise indicated by the metal plate on the

2-3