Tektronix 323, Инструкция по эксплуатации

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Performance Check— Type 323
ing edge of the calibrator waveform (two microseconds or
less risetime).
39. Check Calibrator Repetition Rate
REQUIREMENT-750 hertz, ± 2 5 0 hertz.
a. Change the following control settings:
TRIGGER + AUTO
TIME/DIV .2 ms
X I0 HORIZ MAG Pushed in
b. Position the start of the trace to the left vertical line
of the graticule.
c. CHECK— CRT display for duration of one cycle between
5 and 10 divisions (repetition rate 750 hertz, ± 2 4 0 hertz).
40. Check Calibrator Duty Cycle
REQUIREMENT—40% to 60%.
a. Set the TIME/DIV switch to .1 ms.
b. Set the VARIABLE TIME/DIV control for one complete
cycle in 10 divisions.
c. CHECK— CRT display for length of positive segment
of the square wave between four and six divisions (duty
cycle 40% to 60%).
41. Check Calibrator Voltage Output
REQUIREMENT—0.5 volt, ± 1 % .
a. Change the following control settings.-
VOLTS/DIV .1
TIME/DIV
5 ms
VARIABLE TIME/DIV CAL
e. Set the TRIGGFR control for a '.table display.
f. Position the top of the waveform onto the display area
with the vertical POSITION control.
g. CHECK— Difference between the standard amplitude
calibrator output level and the Type 323 calibrator output
level is 0.05 division (about one trace width) or less (0.5
volt, ± 1 % ; see Fig. 5-7).
Fig. 5 -7 . Typical CRT d isp la y w hen checking vo lta g e o u tput o f c a li­
b rator.
NOTE
b. Connect the CAL OUT connector (side panel) to the
unknown input connector of the standard amplitude cali­
brator with the 18-inch BNC to banana plug patch cord.
c. Set the standard amplitude calibrator for a positive
0.5 volt DC output in the mixed mode.
d. Connect the standard amplitude calibrator output con­
nector to the VERT INPUT connector with a 42-inch BNC
cable.
The procedure given in step 4 o f the C alibration
section (Section 6) provides a more accurate
method o f checking the voltage at the CAL OUT
jack.
This completes the performance check of the Type 323.
If the instrument has met all performance requirements given
in this procedure, it is correctly calibrated and within the
specified tolerances.
5-12
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