Table 5. Radio Bearing Pointer Check

connect it to TB 2-19. Remove the lead connected be-

watch (B2) will be no more than 8 seconds.

tween TB 1-15 and TB 1-17. Connect a new lead between

k. Rotate XMTR 2, causing the RBP to rotate through

TB 1-15 and TB 2-18. Connect a new lead between TB

360° at a rate of approximately 2-revolutions-per-minute.

1-17 and TB 2-18.

Any sticking or binding will not cause the RBP to lag the

b. Adjust the power supply (A4) output until signal

XMTR 2 indication by more than 3° (183° including

strength indicator (M3) energizes and shows all black.

phase difference).

The multimeter (A3) will indicate no more than 22 volts.

l. Set primary power S1 to OFF.

c. Slowly reduce the power supply output until signal

14. Tests of Steering Indicator (M1). a. Set multimeter

strength indicator (M3) deenergizes and shows alternating

(A3) to current function.

black and red segments. The multimeter will indicate no

b. Energize the power supply (A4) and increase output

less than 0.5 volts.

until steering indicator (M1) aligns with the first dot

d. Set the power supply for a 0-volt output.

clockwise from center. The multimeter will indicate be-

17. Tests of Compass Power Flag (M4). a. Disconnect

tween 55 and 95 µa.

the leads (B1) connected to TB 2-18 and connect them to

Table 5. Radio Bearing Pointer Check

TB 2-20. Disconnect the leads connected to TB 2-19 and

Gyro Signal Simulator XMTR 2

Test Instrument Radio

connect them to TB 2-21.

Indication

Bearing Pointer Indication

90° ± 1°, 15 minutes

b. Adjust the power supply output until compass power

180° ± 01, 15 minutes

flag (M4) just begins to move toward the out-of-view

270° ± 1°, 15 minutes

position. The multimeter (A3) will indicate no less than

c. Continue to increase the power supply output until

20 volts.

steering indicator (M1) aligns with the second dot clock-

c. Increase the power supply output until compass

wise from center. The multimeter will indicate between

power flag (M4) is fully out of view against the stop. The

138 and 162 µa.

multimeter will indicate between 32 and 40 volts.

d. Set the power supply for a 0-volt output, and reverse

d. Set the power supply for a 0-volt output.

the connections to TB 2-14 and TB 2-15.

18. Tests of Annunciator (M5). a. Reconnect equip-

e. Adjust the power supply output until steering indica-

ment as shown in figure 4.

tor (M1) aligns with the first dot counterclockwise from

b. Disconnect lead connected to TB 2-14 and connect it

center. The multimeter will indicate between 55 and 95

to TB 2-22. Disconnect lead connected to TB 2-15 and

µa.

connect it to TB 2-23.

f. Continue to increase the power output until steering

c. Set the multimeter (A3) to the current range.

indicator (M1). aligns with the second dot counterclock-

d. Adjust the power supply (A4) output until the

wise from center. The multimeter will indicate between

multimeter indicates 140 microamperes. Annunciator

138 and 162 µa.

(M5) cross will not be in full view.

g. Set the power supply output for 0 volt.

e. Increase the power supply output until annunciator

15. Tests of Station Approach Indicator (M2). a. Dis-

(M5) cross is in full view. The multimeter will indicate be-

connect the lead (B1) connected to TB 2-14 and connect it

tween 170 and 230 µa.

to TB 2-17. Disconnect the lead connected to TB 2-15 and

f. Set the power supply for a 0-volt output, and reverse

connect it to TB 2-16.

connections to TB 2-22 and TB 2-23.

b. Adjust the power supply (A4) output until station

g. Repeat d and e above.

approach indicator (M2) aligns with the center dot of the

h. Set power supply for a 0-volt output.

scale. The multimeter (A3) will indicate between 55 and

19. Final Procedure. a. Deenergize and disconnect all

95 µa.

equipment.

c. Adjust the power supply output until station ap-

b. In accordance with TM 38-750, annotate and affix

proach indicator (M2) aligns with the bottom of the scale.

DA Label 80 (US Army Calibration System) to the front

The multimeter will indicate between 138 and 162 µa.

of the MK-994/AR. When the TI is not within the

d. Set the power supply for 0-volt output.

specified tolerances, annotate and affix DA Form 2417

16. Tests of Signal Strength Indicator (M3). a. Discon-

(Unserviceable or Limited Use) tag and return TI to the

nect the lead (B1) connected to TB 2-16 and connect it to

depot for repair.

TB 2-19. Disconnect the lead connected to TB 2-17 and