TM 55-4920-431-13
Turn wave form select switch to sine-wave setting.
r.
Turn sensitivity knob to mid-scale range setting.
s.
t.
Connect output terminals of oscillator to input terminals of counter.
Connect counter power cable to 110 volt source.
u.
v.
Place LOCAL/REMOTE switch on tester to REMOTE.
w.
Turn dc power supply on.
x.
Turn variable output voltage knob clockwise until output meter indicates 24
volts.
Set counter power switch to on.
y.
Set MASTER switch on tester to on (up). Verify that MAIN POWER LED
z.
indicator light comes on.
Adjust oscillator to each % RPM indication shown in table 4-2 and check input
aa.
frequency and current readings.
Decrease the oscillator frequency to zero.
ab.
Set MASTER switch on tester to off (down).
ac.
Disconnect leads from speed frequency input terminals of signal converter ST93480
ad.
and connect to temperature frequency input terminals.
Reconnect negative terminal wire (wire no. 50) to negative terminal of
ac.
SPEED meter.
Disconnect negative terminal wire (wire no. 47) from TEMP meter.
af.
Connect digital multimeter in series with TEMP meter and disconnected wire.
ag.
Check that multimeter mode selector switch is set to read amperes.
ah.
Be careful not to disconnect test wiring or short
out leads. Damage to components or faulty read-
ings can result.
Lay front panel assembly back on case.
ai.
Set MASTER switch on tester to on (up).
aj.
Adjust oscillator to each F indication shown in table 4-3 and check input
ak.
frequency and current readings.
Set MASTER switch on tester to off (down).
al.
am. Disconnect meter leads from TEMP meter circuit.
4-21
