Table 2-3. Troubleshooting - TM-11-6130-429-400034

TM 11-6130-429-40

Table 2-3. Troubleshooting-Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTION ACTION

Adjust to 26 VDC.

Power Supply

Variable Load

Setting

Control

AC ON

Voltage RANGE

180A

Current RANGE

Mode

30A/V

DC CB

Converter

Setting

Control

AN/TYC-39

System select

ON/OFF

NOTE

Voltages and waveforms given in the diagrams are not abso-

lute and may vary slightly between units.

Step 2. 20 kHz Converter (P/O Main Frame) Check (fig. 2-4).

a. Connect 10:1 scope probe ground to C4 + C5 (-) bus; connect probe to collector of Q2. Adjust horizontal and vertical

positions, and trigger level of scope as required to observe display as shown in figure 2-5A.

Check Q1, Q2, Q3 and associated components. Check A2 PCB components (fig. 2-6). Replace defective

components.

b. Leaving scope ground connected to - bus, connect scope probe to collector of Q5. Adjust scope as required to observe

display as shown in figure 2-5A.

Check Q4, Q5, Q6, and associated components. Check A2 PCB components (fig. 2-6). Replace defective

components.

Step 3. Output Power Section (P/O Main Frame) Check.

a. Connect 1:1 scope probe ground to L3-1; connect scope probe to cathode (+) bus bar of CR8, CR9, and CR11. Adjust

scope as required to observe display as shown in figure 2-5B.

Turn OFF and disconnect all equipment. Using multimeter, check CR6, CR7, CR8, CR9, CR10 and CR11 (2 to 3

ohms in forward direction) secondaries of T1 and T2, L3, C14, and C15.

Replace defective component.

b. Using voltmeter, check for +5 0.1 VDC between P1-A3 (+) and P1-A6 (ground) of rear panel.

Check CR12, CR13, CR14, CR15, CR20, CR21, and associated components. Replace defective component.

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