Tektronix 221, Инструкция по эксплуатации

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SWEEP TRIG G ER
Calibration—221 Service
Equipment Required
3. Cable, 50-ohm BNC connectors
1. Constant amplitude signal generator
4. T Connectors, BNC
2. GR to BNC adapter
5. Probe tip to BNC adapter
Control Settings
22. Check/Adjust Auto Preset Triggering
Preset the controls as given in the Preliminary Control
Settings.
a. Set the VO LTS/DIV switch to .1.
21. Check Trigger Slope
b. Set the constant amplitude signal generator for a
five-division display
a. Connect, to the constant amplitude signal generator,
a GR to BNC adapter and a T connector. Use a probe tip to
BNC adapter to connect the signal to the instrument.
Connect the 50-ohm BNC cable to the T connector.
c. Set the SEC/DIV to 5 0 n and the LEVEL/SLOPE to
AUTO-PRESET.
Connect this cable to the EXT TRIG , using a dual banana
plug adapter (GND on adapter to COMMON).
d. Set the VO LTS/DIV switch to 1.
b. Set the INPUT COUPLING switch to DC.
e. Check that the display remains triggered (stable).
c. Set the SEC/DIV switch to 5 /i.
f. Adjust the AUTO PRESET (R214) side panel screw­
driver adjustment fo r a triggered display. See Fig. 5-9.
d. Set the frequency of the constant amplitude signal
generator to 50 kHz.
g. Switch TRIGGER selector to EXT.
h. Check that the display is stable.
e. Set the vertical deflection factor fo r a signal greater
than 6 divisions. i. Set the SEC/DIV switch to 1 ju.
f. Vary the LEVEL/SLOPE control to trigger on the
positive slope o f the display, then the negative slope.
j. Change frequency of constant amplitude signal
generator to 5 MHz.
g. Check that the display is triggered from the top
graticule line to the bottom graticule line.
k. Check that the display remains stable (slight adjust­
ment of AUTO PRESET adjustment o f R214 may be
necessary).
® i
REV. APR 1974
5-11