TB 9-4931-505-24
(6) VOLTS/DIV switch to 50m.
(7) CAL control fully cw (clockwise).
(8) STEP ATTEN BAL (screwdriver) control to midrange.
(9) +INPUT and -INPUT coupling pushbuttons to GND.
(10) Both AC pushbuttons released to DC.
(11) BANDWIDTH LIMIT 10 kHz pushbutton released.
d. Adjust time base unit for a 1 ms sweep.
e. Energize oscilloscope and allow 30 minutes for equipment to warm-up and stabilize.
8. Dc Balance
a. Performance Check
(1) Center trace on oscilloscope graticule centerline, using POSITION control.
(2) Set VOLTS/DIV switch back and forth between 10m and 50m positions. If
trace on oscilloscope shifts, perform b (1) below.
(3) Set VOLTS/DIV switch back and forth between 1m and 5m positions. If trace
on oscilloscope shifts, perform b (2) below.
(4) Set VOLTS/DIV switch back and forth between 5m and 10m positions. If trace
on oscilloscope shifts, adjust front panel STEP ATTEN BAL control for minimum trace
shift.
(5) Rotate VOLTS/DIV CAL control throughout its range. If trace on oscilloscope
shifts, perform b (3) below.
(6) Reset CAL control to detent position (fully cw).
b. Adjustments
(1) Adjust R112 (fig. 1) for minimum oscilloscope trace shift.
(2) Adjust R212 (fig. 1) for minimum oscilloscope trace shift.
(3) Adjust R194 (fig. 1) for minimum oscilloscope trace shift while rotating CAL
control throughout its range.
9. Amplifier Gain and Vertical Deflection
a. Performance Check
(1) Connect calibrator output to TI +INPUT.
(2) Set VOLTS/DIV switch to 1 mV and release input coupling +GND pushbutton.
(3) Adjust calibrator frequency to 1 kHz and amplitude for a 5 division vertical
deflection on oscilloscope. If calibrator does not indicate between 1.7145 and 1.8205 mV,
perform b below.
