Tektronix 442, Инструкция по эксплуатации

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Operating Instructions—442 Service
Normal Sweep Operation
1. Preset the 442 controls as follows:
NOTE
See Location and Operation of External Controls,
Connectors, and Indicators for detailed instructions
concerning control operation. When using a 10X
probe, use the 10X window on the VOLTS/DIVknob
skirt. For direct input, use the IX window.
VERT MODE
VOLTS/DIV (both)
VAR (all)
POSITION (all)
SEC/DIV
MAGNIFIER
POWER
INTENSITY
FOCUS
HOLDOFF
SLOPE
LEVEL
SOURCE
CPLG
MODE
CH 1
.1 (10X window)
Calibrated (cw)
Midrange
1 m
XI (button out)
ON
As desired
As desired
ccw
TOUT
ccw
CH 1/CH 2
AC (out)
AUTO
2. Connect the PROBE ADJ signal (via the probe
supplied with the 442) to the Channel 1 or X input
connector.
3. Set the Channel 1 AC-GND-DC switch to select the
desired method of coupling the input signal to the
preamplifier circuit. With the PROBE ADJ output signal
use DC. AC coupling will cause tilting of square waves
below about 1 kHz (100 Hz with a 10X probe).
Figure 2-11. Display of 0.5 V PROBE ADJ output signal.
Applications
Peak-to-Peak Voltage Measurements
To make a peak-to-peak voltage measurement, use the
following procedure:
1. Connect a test signal to either Channel 1 or Channel
2 input connector.
2. Set VERT MODE switches to display the channel
selected.
3. Set the VOLTS/DIV switch to display about 5
divisions of waveform amplitude.
4. Set the Triggering controls to obtain a stable
triggered display. Set the SEC/DIV switch to a position
that displays several cycles of the waveform.
4. Adjust the Channel 1 VOLTS/DIV switch to obtain
the desired display amplitude while adjusting the Channel
1 POSITION control to locate the display within the crt
viewing area.
5. Adjust the LEVEL control for a stable display.
6. Adjust the SEC/DIV switch to obtain the desired
display. Using the PROBE ADJ output signal, the display
should appear as illustrated in Figure 2-11 (use a 10X
probe with a VOLTS/DIV switch setting of .1 and a
SEC/DIV switch setting of .5 m).
NOTE
Verify correct probe compensation (see beginning
of Operator’s Adjustments and Checks).
5. Turn the vertical POSITION control so the lower
portion of the waveform coincides with one of the
graticule lines below the center horizontal line and the top
of the waveform is in the viewing area. Use the horizontal
POSITION control to move one of the upper peaks in
alignment with the center vertical graticule line (see
Figure 2-12).
6. Measure divisions of vertical deflection from peak-
to-peak. Verify that the VOLTS/DIV VAR control is in the
fully clockwise calibrated detent position.
NOTE
This procedure may also be used to meausre
between two points on the waveform rather than
peak-to-peak.
2 -1 0
REV A MAY 1980