Table 3-2. Operational Test

TM 11-6665-245-34

Table 3-2. Operational Test

Normal Results

Procedures

NOTE

Procedures 1 through 7 must be repeated for each

probe.

Set selector switch in the following positions in sequence.

Meter scale (change window) shows OFF-BATT. Needle in-

BATT

dicates in the BATT area.

b. Meter scale shows red, 1 M scale. Needle is at zero after 1 or 2

b. 1M

seconds.

c. Meter scale shows orange, 100K scale. Needle is at zero.

c. 100K

d. Meter scale shows magenta, 10K scale. Needle is at zero.

d. 10K

e. Meter scale shows yellow, 1 K scale. Needle is at zero.

e. 1K

Meter needle pegs upscale.

2. Disconnect handles and place probe window on check

source.

Meter needle moves to zero when METER RESET switch is held

3. Set selector switch to 10K and press METER RESET

down; moves upscale when METER RESET switch is released.

pushbutton immediately on changing scales.

4. Connect headphones to panel connector and listen while

Clicking in headset can be heard to increase and decrease with

needle swing.

moving source back and forth on probe window to max-

imize needle indication.

Needle moves downscale to very low reading.

5. Remove headphones and then set selector switch to 100K

position.

Needle moves to zero or very low scale reading,

6. Switch to 1M position.

CAUTION

Be careful when allowing light to fall on bottom of

main probe. Do not allow meter needle to peg or

damage to the photomultiplier tube may result.

7. Allow light to hit probe window area while watching meter

Needle remains at zero.

needle. If needle goes upscale, immediately cover pro-

be window area, removing light. If needle does not go

upscale, increase light to window area.

Meter lights when switch is held down,

8. Press meter light switch on handle while watching for light

at top of meter scale.

first by installing two good batteries. Be careful to

assured that the equipment is working properly

keep probe window area shaded from light after

and can go for calibration. If an item or function

the equipment is turned on. If main or x-ray probe

fails the test, this will then develop symptom or a

light barrier is damaged, photomultiplier tube may

combination of symptoms to use in the

be destroyed from excess current. The auxiliary

troubleshooting table 3-3. To use the table, follow

probe is tested using a light source to find light

the directions in the procedures column to obtain

leaks rather than an electrical test as done with

the results in the normal results column. Start

the main probe.

REPAIR OF RADIACMETER

Section Il.

3-6. Removal and Replacement of Cover

3-7. Removal and Replacement of PCB

Assembly (Figure 3-4)

A s s e m b l y (Figure 3-4)

The cover assembly of the radiacmeter consists

a. Loosen six screws on the radiacmeter until

of the meter panel and all mounted hardware in-

the panel and case can be separated. The selector

cluding the printed circuit board and electronics

switch must be in the OFF position.

inside the case. In order to remove and replace

b. Remove connector J2 that connects the

the cover assembly, simply loosen the six screws

wiring harness to the PCB by grasping the con-

nector with the thumb and forefinger and pulling

which hold the panel and case together.

the connector.

Change 1

3-6