Maintenance of Printed Circuit Board

TM 11-6625-539-14-4

14.

Lock washer

1. Setscrew

27.

Variable resistor R15

40.

Flat washer

15.

Flat washer

2. Knob

28.

Variable resistor R13

41.

Screw

16.

Nut

3. Setscrew

29.

Variable resistor R35

41.

Lock washer

17.

Toggle switch S5

30.

Screw

4. Knob

43.

Flat washer

18.

Nut

31.

Lock washer

5. Nut

44.

Bracket

19.

Lock washer

32.

Standoff spacer

6. Red test jack J1

45.

Printed circuit board

20.

Flat washer

33.

Bracket

7. Black test jack J2

46.

Captive screw

21.

Nut

34.

Bracket

8. Yellow test jack J3

47.

Lock washer

22.

Toggle switch S4

35.

Screw

9. Screw

48.

Flat washer

23.

Nut

36.

Lock washer

10. Nut

49.

Front panel

24.

Lock washer

37.

Meter assembly

11. Lock washer

25.

Flat washer

38.

Nut

12.Transistor socket X1

26.

Lock washer

39.

Lock washer

13. Nut

Figure 7-4. Front panel assembly, exploded view.

d. Take care to prevent solder from shorting

7-12. Maintenance of Printed Circuit Board

across circuit paths on the board. This can cause

a. Remove the printed circuit board for mainte-

circuit path cracks that result in hard-to-locate

nance as described in paragraph 711a.

defects of the equipment.

b. Replace printed circuit board components

e. Printed circuit board installation is described

only if troubleshooting indicates that they are

in paragraph 7-11c.

faulty.

f. Circuit connections between the board and

c. Take care to prevent overheating heat-sensi-

other electronic components are illustrated in fig-

tive components when soldering them to the

ure 7-5.

printed circuit board. Use a heat sink between the

g. Identification of printed circuit board compo-

component. and the solder connection when in-

nents is provided in figure 7-6. To locate a particu-

stalling these components.

7-7