Section VI. TESTING PROCEDURES

TM 11-5825-270-23

Section VI. TESTING PROCEDURES

4-18. General

clockwise, TIME DELAY control A2R32 (fig. 2-1) to the

desired delay, and the RF TUNE control (fig. 2-1) to the

operating frequency (table 2-2).

This section contains test procedures that determine

(2) Set the POWER switch to ON, then

whether the performance of the equipment is

momentarily press the ALARM SIL switch.

satisfactory.

These tests are performed after an

(3) Rotate

the

ATTEN

control

assembly has been replaced, following the replacement

counterclockwise until a reading is obtained on the

procedures in sections IV and V.

CARRIER LEVEL meter.

4-19. Test Equipment

(4) Carefully adjust the RF TUNE control to get

a maximum meter reading.

(5) Adjust

SENSITIVITY

control

A3R7

The test equipment required for the testing procedures is

counterclockwise to get a meter reading of 0 dB.

listed in table 4-1.

(6) Set CARRIER control A2R22 (fig. 2-1) to the

4-20. Performance Testing

desired threshold level. The receiver should now be in

its normal state, with the NORM indicator on and the

a. Each procedure is preceded by instructions for

ALARM indicator off.

(7) Rotate

SENSITIVITY

control

A3R7

setting up and interconnecting the applicable test

counterclockwise to reduce the meter reading to 1 dB

equipment to the equipment under test.

b. In performing the tests, follow the procedure

less than the setting of CARRIER control A2R22. After

the delay set by A2R32 the NORM indicator will go off

steps in the order given and set all controls accurately.

c. At the end of testing set the POWER switch to

and the ALARM indicator will go on.

(8) Rotate

SENSITIVITY

control

A3R7

OFF, disconnect all test equipment and restore the

clockwise to get a meter reading of 0 dB. The NORM

equipment to its normal operational configuration.

indicator will be on and the ALARM indicator will be off.

4-21. Monitor Receiver Test Procedures

(9) Perform the maintenance turn on procedure

of table 4-2.

The following list gives the test procedures required after

4-23. RF Amplifier PCB Test Procedure.

replacement of a unit or assembly. The switch bracket

test procedure is required for organizational level

a. Test Equipment and Material.

maintenance, but the switch bracket replacement is

(1) Electronic Counter Mainframe TD-1209U.

performed by direct support maintenance personnel

(2) Electronic Counter Module TD-1211/U.

(refer to chapter 5).

b. Test Connections and Conditions.

a. Monitor Receiver. Perform the post installation

(1) Connect the frequency counter to A3TP2

(fig. 2-1).

adjustment procedures in chapter 2.

b. Switch Bracket Assembly.

Perform the

(2) The equipment should be connected in its

operational condition, with the POWER switch set to

procedure of paragraph 4-22.

c. RF Amplifier PC. Perform the procedure of

OFF.

c. Procedure.

paragraph 4-23.

d. If. Amplifier PCB. Perform the procedure of

(1) Check that crystal Y1 (fig. 2-1) is the correct

frequency. The crystal frequency equals 4.4 MHz minus

paragraph 4-24.

e. Audio Amplifier PCB. Perform the procedure of

the transmitter frequency. The crystal frequency is

marked on the top of the crystal.

paragraph 4-25.

f. Power Supply Assembly.

Perform the

(2) Set the POWER switch to ON, then

momentarily press the ALARM SIL switch.

maintenance turn on procedure of table 4-2.

(3) Adjust A3C13 (fig. 2-1) to provide the correct

4-22. Switch Bracket Assembly Test Procedure

frequency 10 Hz.

(4) Carefully adjust the RF TUNE control (fig.

a. Test Equipment and Material. None.

2-1) to get a maximum reading on the CARRIER LEVEL

b. Test Connections and Conditions. The equip

meter.

(5) Adjust SENSITIVITY control A3R7 (fig. 2-1)

ment should be connected in its operational condition,

to get a CARRIER LEVEL meter reading of 0 dB.

with the POWER switch set to OFF.

c. Procedure.

(6) Perform the maintenance turn on procedure

of table 4-2.

(1) Set RF ATTEN control (fig. 2-1) fully

clockwise, SENSITIVITY control A3R7 (fig. 2-1) fully

4-10