Tektronix 442, Инструкция по эксплуатации

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Calibration Procedure—442 Service
Performance Check
AMPLITUDE
CALIBRATOR
442 OSCILLOSCOPE
COUPLER
2 3 7 4 - 5 A
Figure 4-1. Vertical deflection accuracy test setup.
PROCEDURE
NOTE
d. CHECK—Channel 2 deflection accuracy for the
settings listed in Table 4-2 within 3% (+20°Cto +30°C).
Set CH 2 POSITION as required.
The following procedure is arranged to be per­
formed in its entirety, starting with Step 1 and
proceeding in sequence to the end. This ensures the
correct 442 and test equipment settings and connec­
tions for each step.
1. Channel 1 and Channel 2 Deflection Accuracy
Check
a. Connect the test equipment as shown in Figure 4-1
and apply an unterminated 10 mV, 1 kHz Amplitude
Calibrator signal to the CH 1 and CH 2 input connectors.
SettheCH 1 AC-GND-DC switch to DC and the CH 2 AC-
GND-DC switch to GND. In the remainder of this step, set
the CH 1 and CH 2 POSITION control (as appropriate) to
center the display within the graticule area.
b. CHECK—Channel 1 deflection accuracy for the
settings listed in Table 4-2 within 3% (+20°C to +30°C).
Adjust INTENSITY and all POSITION controls as re­
quired. For best results in Steps 1 and 2, leavethe LEVEL
control fully clockwise for a free-running display.
c. Set:
Amplitude Calibrator
Output
10 mV
442
AC-GND-DC (CH 1)
AC-GND-DC (CH 2)
VERT MODE
POSITION (CH 2)
GND
DC
CH 2
For centered display
Table 4-2
VERTICAL DEFLECTION ACCURACY
VOLTS/DIV
Setting
(IX Window)
Amplitude
Calibrator
Output
Vertical
Deflection
(Divisions)
±%
Tolerance
(Divisions)
2 m
10 mV
5
4.85 to 5.15
5 m 20 mV
4 3.88 to 4.12
10 m
50 mV 5 4.85 to 5.15
20 m .1 V
5 4.85 to 5.15
.2 1 V
5
4.85 to 5.15
2 10 V
5 4.85 to 5.15
2. Channel 1 and Channel 2 VAR (Variable)
VOLTS/DIV Range Check
a. Set the amplitude calibrator for a 0.1 volt output.
b. Set the Channel 1 and Channel 2 VOLTS/DIV
switches to 20 m (IX window).
c. CHECK—Display amplitude reduces from 5
divisions to less than 2 divisions when the Channel 2 VAR
control is rotated to its fully counterclockwise position.
R E V A M A Y 1980
4-5