TB 9-4931-505-24
10. Overdrive Recovery
a. Performance Check
(1) Set VOLTS/DIV switch to 2 and adjust time base unit sweep rate for a 10 ms sweep.
(2) Set time base unit sweep mode to normal and trigger source to external.
(3) Connect oscilloscope calibrator SOURCE/MEASURE CHAN 1to TI +INPUT
using 50 feedthrough termination.
(4) Connect oscilloscope calibrator SOURCE/MEASURE CHAN 5 to time base
unit external input.
(5) Adjust oscilloscope calibrator frequency for 10 Hz and amplitude for a 5 division
vertical deflection on oscilloscope.
(6) Set VOLTS/DIV switch to 1m and time base unit for a 20 s sweep.
(7) Press ZERO Vc REF pushbutton and hold while adjusting POSITION control
to center trace on oscilloscope graticule centerline and then release. If trace does not return
to centerline within 1.5 divisions when released, perform b (1) below.
(8) Move cable from TI +INPUT to -INPUT.
(9) Press +INPUT coupling pushbutton to GND and release -INPUT coupling
pushbutton to DC (out positions).
(10) Repeat technique of (7) above and, if necessary, perform b (2) below.
b. Adjustments
(1) Adjust C104 (fig. 1) until trace returns to graticule centerline within 1.5
divisions in 0.1 ms (final adjustment made in paragraph 12 b) (R).
1.5
(2) Adjust C204 (fig. 1) until trace returns to graticule centerline within
divisions in 0.1 ms (final adjustment made in paragraph 12 b) (R).
11. Input Compensation
a. Performance Check
(1) Connect oscilloscope calibrator SOURCE/MEASURE CHAN 1 to TI -INPUT
connector, using standardizer.
(2) Set VOLTS/DIV switch to 50m.
(3) Adjust time base unit for a few cycle display and set triggering source switch to left.
(4) Adjust oscilloscope calibrator square wave output for 1 kHz and amplitude for a
6 division square wave display on oscilloscope.
(5) Adjust standardizer for an optimum square wave display on oscilloscope. If
square wave indicates roll off or overshoot, perform b (1) below.
