Tektronix 422, Instruction Manual

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Performance Check/Calibration—Type 422 AC-DC
h. ADJUST—C527 (see Fig. 5-27) fo r one marker each
division (use low-capacitance screwdriver).
i. Repeat parts c through h o f this step until optimum
tim ing is obtained.
50. Check Normal Sweep Timing Accuracy
a. Push th e X 1 0 M A G s w itc h in.
CAUTION
To prevent permanent damage to the CRT phosphor
at slow sweep rates position the baseline of the
marker display below the viewing area.
b. CHECK—Using the T IM E /D IV switch and time mark
generator settings given in Table 5-5, check sweep timing
w ithin 0.24 division (within 3%) over the middle eight divi­
sions o f the display. Adjust the LEVEL control as necessary
to obtain a stable display.
51. Check Magnified Sweep Timing Accuracy
a. Pull the X10 MAG switch.
b. CHECK—Using the T IM E /D IV switch and time-mark
generator settings given in Table 5-6, check magnified
tim ing w ithin 0.4 division (within 5%) over the middle eight
divisions o f the total magnified sweep length.
c. Disconnect all test equipment.
TABLE 5-5
Normal Sweep Timing
TIM E/D IV switch
setting
Time-mark
generator output
CRT display
(markers/division)
.5 [is 0.5 microsecond
1
1 [is 1 microsecond
1
2 [is 1 microsecond
2
5 [is 5 microsecond 1
10 [is 10 microsecond 1
20 [is 10 microsecond 2
50 [is 50 microsecond
1
.1 ms 0.1 millisecond 1
.2 ms 0.1 millisecond
2
.5 ms 0.5 millisecond
1
1 ms 1 millisecond
1
2 ms 1 millisecond
2
5 ms 5 millisecond
1
10 ms 10 millisecond
1
20 ms
10 millisecond
2
50 ms 50 millisecond 1
.1 s 0.1 second 1
,2 s 0.1 second 2
,5 s 0.5 second 1
52. Check Gate Output Signal
a. Change the follow ing control settings:
TRIGGERING Source CH 1 & 2
T IM E /D IV 1 ms
X I 0 MAG Pushed in
b. Connect the GATE OUT connector to the input of
the test oscilloscope w ith a 42-inch BNC cable.
c. Set the test oscilloscope fo r a vertical deflection of
0.1 volt/division and a sweep rate o f tw o milliseconds/
division.
d . CHECK—Test oscilloscope fo r five divisions or
greater amplitude (0.5 volt or greater in amplitude; see Fig.
5-28). Gate duration should be between 5.2 and 6.05 divi­
sions (10.4 to 12.1 times the T IM E /D IV switch setting).
e. Disconnect the test oscilloscope.
53. Check Chopped Operation
a. Change the follow ing control settings:
Vertical Mode CHOPPED
T IM E /D IV 1 jus
b. Position the traces about fo ur divisions apart w ith the
Channel 1 and 2 POSITION controls.
TABLE 5-6
Magnified Sweep Timing Accuracy
T IM E /D IV switch
setting
Time-mark
generator output
CRT display
(markers/division)
.5 |ls 50 nanosecond 1
1 [is .1 microsecond 1
2 [is .1 microsecond 2
5 [is .5 microsecond 1
10 [is 1 microsecond
1
20 [is 1 microsecond 2
50 [is
5 microsecond 1
.1 ms 10 microsecond
1
.2 ms 10 microsecond 2
.5 ms 50 microsecond 1
1 ms .1 millisecond 1
2 ms .1 millisecond 2
5 ms .5 millisecond 1
10 ms
1 millisecond 1
20 ms
1 millisecond 2
50 ms
5 millisecond 1
.1 s 10 millisecond 1
.2 s
10 millisecond 2
.5 s
50 millisecond 1
5-33