Maintenance Turn On Procedure

TM 11-5825-270-23

level troubleshooting has been performed (i.e., fuses

operational condition.

and lamps have been checked and were either good or

4-7. Maintenance Turn On Procedure

continuously blowing).

WARNING

a. A maintenance turn on procedure is provided

Always turn the power off and

(table 4-2) to assist in a systematic approach to isolating

remove the ac power cord from J2 at

malfunctions.

These procedures reference the

the back of the receiver before

applicable malfunction in troubleshooting table 4-3.

performing any of the replacement

Each step of the maintenance turn on procedure

procedures.

assumes that all previous tests were performed

satisfactorily.

NOTE

b. Troubleshooting procedures should be preceded

After a fault has been located and

by a thorough visual inspection and a check for burnt or

cleared, carry out all tests that are

discolored resistors, broken or disconnected wiring or

referenced

the

replacement

other abnormalities that may indicate the circuit at fault.

procedures.

c. The procedures in table 4-2 assume that input

power to the monitor receiver is correct and that operator

Table 4-2. Maintenance Turn On-Procedure

Step

Procedure

Observation

Corrective Action

Examine all connections at rear of

All connections will be secure.

Tighten as required.

receiver.

Verify that the NDB transmitter

None.

is operating satisfactorily.

Set POWER switch to ON, then

a. Indicating fuse will be off.

a. Refer to table 4-3, malfunction 1.

momentarily press the ALARM SIL

b. POWER indicator will be on.

b. Refer to table 4-3, malfunction 2.

switch.

c. NORM indicator will be on and

c. If both indicators are off refer

ALARM indicator will be off.

to table 4-3, malfunction 4. If

NORM indicator is off and

ALARM indicator is on, refer to

table 4-3, malfunction 5.

d. Remote alarm will be off.

d. Refer to table 4-3, malfunction 6.

e. CARRIER LEVEL meter will

e. Refer to table 4-3, malfunction 7.

read 01 dB.

Set AUDIO LEVEL control to

Keying will be heard in the loud-

Refer to table 4-3, malfunction 8.

approximately midposition.

speaker.

Turn front panel latch and swing

None.

the front panel door open.

During the keying sequence press

After the delay set by TIME DE-

a. If the delay is wrong refer to

the ALARM TEST switch and hold

LAY control A2R32 (fig. 2-1) the

table 4-3, malfunction 9.

it pressed.

NORM indicator will be on, the

b. If the receiver does not alarm refer

aural alarm will sound, and the

to table 4-3, malfunction 10

remote alarm will be on.

c. If there is no aural alarm refer

to table 4-3, malfunction 11.

d. If the NORM and ALARM indicators

are both off refer to table 4-3,

malfunction 4.

Press the ALARM SIL switch.

The aural alarm will be off.

Refer to table 4-3, malfunction 12.

Release the ALARM TEST switch.

a. Norm indicator will be .on and

a. If both indicators are off refer

ALARM indicator will be off.

to table 4-3, malfunction 4. if

NORM indicator is OFF and

ALARM indicator is on refer to

table 4-3 malfunction 13.

b. Remote alarm will be off.

b. Refer to table 4-3, malfunction 6.

c. CARRIER LEVEL meter will

c. Refer to table 4-3, malfunction 7.

read 0 dB.

4-2