Indicators.

Function

Control

Switch

position

Action

performance of trans-

conductance (GM)

test.

SIGNAL-VR control--------------------- Permits accurate adjustment of ac signal

level (indicated on the SIGNAL

meter). In test of voltage-regulator

tubes, permits adjustment of maxi-

mum and minimum currents through

t h e tube (indicated on the PLATE

meter).

Quality SHUNT control -------------- When set to the position specified on the

tube test data roll chart, shunts PER-

CENT QUALITY meter with proper

resistance to perform quality (GM)

test.

GM CENTERING control ------------ With GM-SIGNAL RANGE switch in

position F and the quality SHUNT

control set in accordance with tube

test data, permits zero calibration of

the PERCENT QUALITY meter for

transconductance (GM) test.

b. Indicators.

Indicator

Function

PERCENT QUALITY meter ------- Indicates transconductance of amplifier

tube under test.

FILAMENT VOLTS meter ---------- Indicates ac filament voltage supplied to

tube under test.

GRID BIAS VOLTS meter ----------- Indicates grid-bias voltage supplied to

tube under test.

PLATE meter -------------------------- Indicates plate voltage supplied to tube

under test.

SCREEN VOLTS meter ------------- Indicates screen grid voltage supplied to

tube under test.

SIGNAL meter ------------------------- Indicates ac signal level supplied to tube

under test.

PILOT lamp ------------------------ Glows when tube tester is connected to

ac power source and power ON-OFF

switch is in ON position.

FIL. CONT. SHORT lamp ------- Glows to indicate short-circuited ele-

ments or filament continuity in tube

under test.

Note. On some equipments this lamp is

marked SHORT.