TB 9-6625-2083-24
h. Set CH 1 VOLTS/DIV switch from 20 to 5 mV. If trace shifts vertically from center
horizontal graticule line, adjust CH 1 STEP ATTEN BAL adjustment (front panel)
for no shift.
i. Set CH 1 VOLTS/DIV switch to 50 mV, then to .1 mV. If trace shifts vertically
from center horizontal graticule line, adjust R28 (fig. 6) for no shift.
j. Set MODE switch to CH 2 and repeat (g) through (i) above, using CH 2 controls and
STEP ATTEN BAL adjustment. Adjust R128 (fig. 6) for CH 2 in (i) above, if necessary.
Figure 6. Vertical preamp board adjustment locations - bottom view.
21. CH 1 and CH 2 Gain
a. Performance Check
(1) Set VOLTS/DIV switches to 20 mV and MODE switch to CH 1.
(2) Connect oscilloscope calibrator SOURCE/MEASURE CHAN 1 to both TI CH 1
and CH 2 input.
(3) Set oscilloscope calibrator for a CHAN 1, VOLTAGE mode output of 100 mV
and output frequency of 1 kHz.
(4) Rotate oscilloscope calibrator knob located below EDIT FIELD pushbutton for 5
divisions of vertical display on TI. If oscilloscope calibrator Err display readout does not
indicate within limits specified in first row of table 7, perform b (1) and (2) below.