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.
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