Front Panel Assembly Removal and installation

TM 11-6625-539-14-4

panel assembly is removed from the case, clean

and inspect it as follows:

(1) Remove any dust from the electronic com-

ponents with vacuum cleaning equipment.

(2) Inspect the electronic components and wir-

ing of the test set for broken leads, corroded

terminals, and faulty solder connections. Replace

damaged leads and resolder broken connections.

(3) Check all panel-mounted components for

loose mounting. Tighten mounting hardware as

EL6625-539-14-4-TM-14

required.

Beta Adjustments Setup

Figure 7.2.

(4) If any components are obviously damaged,

replace them.

(4) Insert the test leads of the multimeter into

remote test jacks B, G and E, S.

c. Installation.

(5) Adjust variable resistor R34(10) to obtain

(1) Position the front panel assembly (1, fig. 7-

1) part way into the case.

a zero or 0.0 reading on the multimeter.

(6) Repeat steps (2) through (5) above and

(2) Connect the terminals (12 and 13) of the

readjust if necessary.

battery lead (4) to the connectors at the back of

the case. The black negative lead connects to the

(7) Remove the transistor and disconnect the

upper right terminal, the white positive lead con-

multimeter from the transistor test set.

nects to the lower left terminal when you are

e. Transconductance Adjustment

facing the inside of the case.

(1) Adjust the METER ZERO control to zero

(3) Push the front panel assembly into the

the meter.

case until the panel is fully seated. Tighten the six

(2) Connect a 460-ohm ±1 percent resistor

captive screws to secure the panel to the case.

across the C, D, and B, G remote test jacks.

(4) Install the cover on the test set.

(3) Adjust the RANGE switch to the

X 1.0 position.

7-10. Maintenance of Test Set Case

(4) Adjust the FUNCTION switch to

a. Disassemble (fig. 7-3). Disassemble the test

FET position.

set case only to the extent necessary to replace

(5) Adjust variable resistor R12 (11) to provide

defective parts. Proceed as follows:

midscale deflection of the meter (20 on top

(1) Remove the two screws (1) that secure

scale). This will adjust the transcon-

each of the catches (2) to the cover (5); remove the

ductance of the unit.

catches.

7-9. Front Panel Assembly Removal and in-

(2) Pull out the accessory bracket assembly

stallation

(3). Unsrew the spacers (4) from the cover.

a. Removal. All operating components and parts

(3) Loosen the six captive screws (7) and

of the test set, with the exception of the batteries,

remove the battery compartment cover (11) from

are mounted on the front panel assembly. For

the test set case (37). If the captive screws are

service or calibration, you must remet'e the front

damaged, remove the preformed packings (8) and

panel assembly as follows:

unscrew the screws from the cover. Remove the

(1) Remove the cover from the test set.

flat washers (9) and lock washers (10).

(2) Loosen the six captive screws (2, fig. 7-1)

(4) Remove the six batteries (12) from the

that secure the front panel assembly to the case.

battery compartment in the rear of the case. If

(3) Pull outward on the front panel assembly

the battery contacts (19 and 20) are corroded or

to disengage it from the case. Remove only far

bent, remove them by removing screws (13), lock

enough to allow access to disconnect the terminals

washers (14), nuts (15), clips (16), and flat washers

(12 and 13) of the battery lead (4) from the connec-

(17 and 18). Remove battery interconnecting leads

tors at the back of the case. Disconnect the bat-

(21) and the cushioning pads (22).

tery lead terminals and remove the front panel

(5) If the catch strikes (24) are damaged,

assembly fully from the case.

remove the two screws (23) that secure each of the

strikes to the case.

b. Cleaning and Inspection. After the front

7-4 Change 1