Figure 13. Simplified selector switch diagram.

element shorts within a tube and the positions

S109 (fig. 14) shows the shorts test section of

o f the FUNCTION SWITCH in which the

the switch in position 1. In this position, the

SHORTS lamp will glow for a particular short:

cathode, the filament, and the suppressor grid

of the tube under test are in contact with seg-

ment Y; the screen grid, the plate, and the

control grid are in contact with segment Z.

Any shorted condition between an element on

segment Y and elements on segment Z com-

pletes the circuit between C102 and E101, and

SHORTS lamp E101 will glow. Rotation of . .

s w i t c h from position 2 through position 5

changes the grouping of the elements on the

two segments. Different types of shorts will

cause the neon lamp to glow on different posi-

tions of the switch; that is, a screen-to-suppres-

sor short will cause the lamp to glow in all five

positions while a control grid-to-plate short

will cause a glow only on position 4. The fol-

lowing chart shows the various possible inter-

Figure 13. Simplified selector switch diagram.