Vertical Deflection Accuracy - Tektronix 442 Service Manual

AMPLITUDE
CALIBRATOR
Calibration Procedure—442 Service
Performance Check
COUPLER
PROCEDURE
NOTE
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 connéc-
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.
Set the CH 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, leave the LEVEL
control fully clockwise for a free-running display.
c. Set:
Amplitude Calibrator
Output 10 mV
442
AC-GND-DC (CH 1) GND
AC-GND-DC (CH 2) DC
VERT MODE CH 2
POSITION (CH 2) For centered display
REV A MAY 1980
d. CHECK—Channel 2 deflection accuracy for the
settings listed in Table 4-2 within 3% (+20°C to +30°C).
Set CH 2 POSITION as required.
Table 4-2
VERTICAL DEFLECTION
ACCURACY
VOLTS/DIV | Amplitude
Vertical +%
Setting Calibrator
Deflection Tolerance
(1X Window)
Output (Divisions) | (Divisions)
—
——————
2m 10 mV
4.85 to 5.15
3.88 to 4.12
4.85 to 5.15
4.85 to 5.15
4.85 to 5.15
4.85 to 5.15
5m 20 mV
10m 50 mV
20m TV
2 1V
2 10V
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