User's Manual

a. Perform the operations described in paragraphs 15 and 16.

b. Operate the FUNCTION switch to the TEST position.

c. Set the PLATE-SCREEN RANGE switch to the position

specified on the tube test data roll chart.

d. Adjust the PLATE fine control until the PLATE meter in-

dicates the exact voltage specified on the tube test data roll chart.

Red calibration marks on the meter scales facilitate this adjust-

ment.

e. Operate the quality SHUNT control to the number specified

on the tube test data roll chart.

f. Operate the GM-SIGNAL RANGE switch to the position

noted on the tube test data roll chart.

g. For the TV–2/U, aline the dot on the knob of the GM CEN-

TERING control with the dot on the panel. For the TV-2A/U

and TV-213/U, aline the line marking on the GM CENTERING

knob with the line marking on the panel.

h. If the tube under test is a diode, hold down the PRESS TO

TEST P2 switch. If the tube under test is a multigrid tube, hold

down

both the P2 and P3 switches.

i. Read the PERCENT QUALITY meter. If the indication is

below the minimum limit given on the tube test data roll chart,

discard the tube. Tubes that border on the minimum limit may be

usable but should be replaced soon.

Note. When testing some diodes, the PERCENT QUALITY meter will

deflect off scale. This is a normal condition when the emission of the tube is

far in excess of that required by tube specifications. If the need for balancing

such a diode is present, reduce the setting of the quality SHUNT control until

the PERCENT QUALITY meter reads 100. Observe the new shunt setting

and use this setting to compare diodes of the same type.

j. When the test is completed, set the ON-OFF switch to the

OFF position, remove the tube under test from the test socket,

and return all switches and controls to their safety positions

(par. 15d).

24.

Voltage Regulator and Gas Recifier Test

Use the following procedure to test the voltage regulator (VR)

and gas rectifier tubes under minimum and maximum load con-

ditions. The regulating ability of the tube is computed from the

test results. For testing thyratron tubes, refer to paragraph 26.

a. Perform the operations described in paragraphs 15 and 16.

Set the FILAMENT RANGE and BIAS RANGE switches to the

positions indicated in the tube test data roll chart.

b. Set the PLATE-SCREEN RANGE switch to the position

specified on the tube test data roll chart.