TB 9-6625-2802-35
(2) Connect preamplifier output, CHANNEL
equal to voltage in step (3) above.
OUT 1 (rear panel terminal block) to digital
(5) Turn CAL control fully counterclockwise;
voltmeter (A2) using cable (B2).
the voltage should not be greater than the
measurement in step (3) above divided by
(3) Set dc voltage standard (Al) for a zero-volt
2.5.
output on its one-volt range.
(6) Repeat steps (1) through (5) above for
(4) Set the preamplifier sensitivity range to 1
channel 2.
mV/DIV.
b. Adjustments. No adjustments can be made.
(5) Set the INPUT lever switch to OPR.
12. Frequency Response.
(6) Observe and record the indicated output of
the preamplifier at digital voltmeter (A2).
a. Performance Check.
(7) Set dc voltage standard (Al) for a 50
(1) Set range switch to 50 mV/DIV, INPUT
millivolt output.
switch to OPR and CAL control fully
(8) If there is not a 5 volt difference from the
clockwise.
previous value recorded in step (6),
perform adjustments in b. below.
(2) Set test oscillator (A6) frequency to 10 Hz
sinusoidal and connect to preamplifier.
b. Adjustments. Set CAL resistor R33 (see fig. 2)
for a 5 volt difference from the previous value recorded in
(3) Set CHART SPEED to 5 mm/SEC and
step (6) above (R).
CHANNEL 1 pen to center of grid.
11. Sensitivity Vernier Span.
(4) Adjust amplitude of test oscillator to a full
scale deflection on chart.
Increase
a. Performance Check.
frequency to 40 Hz. The amplitude should
not change more than + 0.5 mm.
(1) Set the preamplifier sensitivity selector
switch to 1 mV/DIV, INPUT switch to OPR
(5) Continue to increase test oscillator
and CAL control fully clockwise.
frequency until amplitude is 35 mm full
scale. The frequency should then be 55
(2) Apply 50 millivolts from the dc voltage
Hz or greater.
standard (Al) to preamplifier input.
(6) Repeat steps 1 through 5 above for
(3) Measure and record the output voltages of
channel 2.
CHANNEL 1 and SIG COMMON on rear
panel terminal strip.
b. Adjustments. No adjustments can be made.
(4) Turn
CAL
control
slightly
13. Power Check.
counterclockwise; observe voltage to be
greater than or
a. Performance Check. Perform the voltage supply
checks by connecting
9