TB 9-6625-2142-40
(33) Press to release VARIABLE (CAL IN) control and turn fully ccw. Crt display
will indicate 1.5 divisions of vertical deflection or less.
(34) Turn VARIABLE (CAL IN) control fully cw.
Crt display will indicate 7.5
divisions of vertical deflection or more.
(35) Press VARIABLE (CAL IN) control to in position.
(36) Set TI mVOLTS/DIV switch to 100. Adjust oscilloscope calibrator output for 6
divisions of vertical deflection on crt.
(37) Adjust sampling sweep unit TIME POSITION control until first dot on front
corner of square wave is at the same level as the positive level of the square wave.
(38) Turn DOT RESPONSE control fully cw. If the first dot on the front corner of
the square wave does not move at least 1 division above the positive level of the square
wave, perform b below.
(39) Turn DOT RESPONSE control fully ccw. If the first dot on the front corner of
the square wave does not move at least 1 division below the positive level of the square
wave, perform b below.
(40) Adjust DOT RESPONSE control until first dot is at same level as the positive
level of square wave.
(41) Press SMOOTH pushbutton and observe that first dot on front corner of square
wave is less than 1.8 divisions from negative level of square wave.
b. Adjustments
(1) Connect oscilloscope No. 2 vertical amplifier INPUT to TI 230 TEST POINT (fig.
2) using X10 probe.
(2) Set oscilloscope No. 2 vertical amplifier VOLTS/DIV switch to .2 V and delaying
time base amplifier TIME/DIV switch to .1 s.
(3) Set sampling sweep unit SWEEP RANGE switch to 5 ms and TIME/DIV
switch to 0.5 ms.
(4) Adjust oscilloscope No. 2 vertical and horizontal controls for positive-going pulse.
(5) Adjust MEMORY GATE WIDTH R460 (fig. 3) for pulse width of between 160
and 180 ns (R)
(6) Disconnect X10 probe from 230 TEST POINT (fig. 2).
9. Delay Range
a. Performance Check
(1) Set oscilloscope calibrator mode to marker and a 10 ns output.
(2) Connect oscilloscope calibrator output to sampling head.
(3) Set sampling sweep unit SWEEP RANGE switch to 50 ns and TIME/DIV
switch to 2.
