Tektronix 442, Инструкция по эксплуатации

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Calibration Procedure—442 Service
Performance Check
d. Set:
VERT MODE CH 1
AC-GND-DC (Channel 1) DC
AC-GND-DC (Channel 2) GND
e. CHECK—Display amplitude reduces from 5
divisions to less than 2 divisions when the Channel 1 VAR
control is rotated to its fully counterclockwise position.
d. CHECK—Duration of one cycle is within ap­
proximately 3.33
/
js
to 6
/
js
(3.3 to 6 horizontal graticule
divisions).
e. Set the LEVEL control fully clockwise.
f. CHECK—Both traces appear simultaneously at
sweep speeds of .5 ms to .5 s (SEC/DIV settings of.5 mto
.5).
f. Return both VAR controls to the fully clockwise
(detent) position and disconnect the Dual Input Coupler g. Set VERT MODE to ALT.
from the test setup.
h. CHECK—Both traces appear alternately at
SEC/DIV settings of .1 /ithrough.5 m (traces are visible at
3. X-A xis D eflection C h eck
thesametimebutmayflickerduetothealternatesweeps).
a. Connect the 0.1 volt Amplitude Calibrator signal
cable to the Channel 1 (X) input connector and set the
INTENSITY control for a barely visible 5-division
amplitude display.
b. Set:
VERT MODE
SOURCE
POSITION (Horizontal)
INTENSITY
CH 2 (X-Y)
X-Y
As required to
view two dots
Barely visible dots
i. Set:
AC-GND-DC (CH 1 & CH 2) DC
VERT MODEf C H I
VOLTS/DIV (CH 1 & CH 2) 10 m (IX)
POSITION (all) As required
SEC/DIV 1 m
j. Connect a 50 kHz Leveled Sine-wave Generator
signal through a 50 Q precision cable, a 50 Q termination,
and a Dual Input Coupler to the Channel 1 and Channel 2
input connectors.
c. CHECK—Distance between the two dots is 5
divisions ±5% (4.75 to 5.25 divisions).
k. Set the generator amplitude to provide a 5-division
display.
d. Disconnect the Amplitude Calibrator signal cable
from the Channel 1 input and set SOURCE to COMP.
I. Set VERT MODE to DIFF and adjust Channel 1 and
Channel 2 VOLTS/DIV VAR controls for a minimum
amplitude display.
4. C H O P , A L T, D IF F and C m rr Function Checks
a. Set:
m. Set the generator output frequency to 1 MHz.
SOURCE
SEC/DIV
VOLTS/DIV (CH 1 & CH 2)
AC-GND-DC (CH 1 & CH 2)
VERT MODE
INTENSITY
POSITION (all)
COMP
1 A
10 m (IX)
GND
CHOP
For visibledisplay
As required
b. Set the POSITION controls to place the traces 4
divisions apart and centered within the graticule area.
n. CHECK—Display amplitude is .5 division or less.
o. Return both VAR controls to the calibrated detent
position (fully clockwise).
p. Disconnect the dual Input coupler from the test
setup.
5. C hannel 1 B andw idth C heck
c. Adjust the LEVEL control for a stable triggered
display.
a. Connect the test equipment to the Channel 1 input
connector as shown in Figure 4-2.
4-6
REV A MAY 1980