Pitch, Roll, and Yaw ILCA Simulator Resistance Test (CRC)

TM 55-4920-430-13

c. Connect a jumper between receptacle pins J3-KK and to J3-AA. The multimeter shall indicate +4

to +5.5 volts dc.

d. Disconnect jumper.

e. Disconnect multi meter.

f. Connect the digital multimeter, set to measure dc volts, to receptacle pins J3-KK and J3-AA.

g. Set BARO ALT switch to 1. The multimeter shaIl indicate .1 to +.1 volt.

h. Set BARO ALT switch to 2. The multimeter shall indicate .1 to +.1 volt.

4-53. Pitch, Roll, and Yaw ILCA Simulator Resistance Test (CRC). (See fig. 4-9.) This test checks

the resistor in the circuit that simulates the impedance of the ILCA servo valve. The measurement is

taken between VALVE HI and VALVE LO pins. Proceed as follows:

a. Set the test set POWER switch to OFF.

b. Measure resistance between receptacle pins as listed below. Use a multimeter set to a resistance

range which shows the reading below half scale. Resistances shall be as listed below:

RECEPTACLE PINS

RESISTANCE (OHMS)

2188 to 2232

J1-JJ to J1-PP

2188 to 2232

J1-NNtoJl-MM

2188 to 2232

J1-HHtoJ1-v

4-54. Pitch ILCA Simulator Performance Tests. (See fig. 4-9. ) This test ensures the test set

provides independent simulation for the two servo amplifiers outputs of the AFCS computer in the

pitch axis. The positive input test simulates the actuator extending. The negative input-test simulates

the actuator retracting. Feedback No. 1, simulates the self-feedback. Feedback No. 2 is one-half of the

cross-feedback. Feedback No. 3 is the other half of the cross-feedback.

a. Positive input test.

(1) Set the test set POWER switch to ON.

(2) Set the SERVO SIMULATION PITCH switch to OPERATE.

(3) Connect the positive terminal of No. 1 dc power supply to one side of the decade resistor. Con-

nect the other side of the decade resistor to receptacle pin J1-JJ. Connect the negative side of the power

supply to receptacle pin J I- PP. Set the decade resistor to 1000 ohms.

(4) Connect the digital multimeter across the decade resistor, positive lead of the multimeter to

the positive output of the power supply. Set the multimeter to the 2 volt dc range.

(5) Adjust the output of the power supply for +0.100 Vdc on the digital multimeter.

NOTE

This applies approximately 0.1 ma of input current through J1-JJ.

(6) Disconnect the digital multimeter from the power supply and decade resistor.

(7) Connect the digital multimeter set to measure 20-volt ac to receptacle pins J1-W (line) and J3-

AA. The multimeter shall indicate less than .03 vat.

(8) Connect No. 2 power supply across receptacle pins J3-A (+) and J1-C.