Tektronix 7B53A, Инструкция по эксплуатации

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7B53A/7B53AN OPTION 5
b. Check for a test oscilloscope display of one or more
negative-going pulses in a group during the vertical sync
pulse interval. The number of pulses is dependent on the
television standard composite video signal being applied to
the plug-in unit. The pulse is very fast; approximately
0.1 µs in width at the 50% amplitude level. Full pulse
amplitude is approximately 2.8 volts.
4. Check TP920 Composite Sync Waveform
a. Connect the 10X probe to TP920.
b. Check test oscilloscope display. The waveform should
be negative-going composite sync occurring at the H rate;
amplitude should be approximately 180 mV. All video,
except burst, should be clipped off.
5. Check Sync Separator Operation
a. Apply various television standard composite video
signals (domestic and closed circuit) to the plug-in unit.
NOTE
If desired, apply only those composite video signais
that will be used at your facility.
b. With the 10X probe connected to TP920, check the
test oscilloscope display for a proper waveform as described
in step 4.
d. Pull the DLY TIME knob outward and set the DLY
TIME switch to the desired position (10µs). Rotate the
DELAY TIME MULT control to intensify the desired
portion of the display. Then, push the DLY TIME knob in
to view the intensified portion.
NOTE
In this mode of operation the delayed sweep is free
running.
7. Check Discrete Line Selector Operation
a. Set the 7B53A/7B53AN OPTION 5 Main Triggering
Amplifier SOURCE switch to TV LINE. Adjust the LEVEL
control to obtain a triggered display.
b. Rotate the DLY'D TRIG control out of the RUNS
AFTER DLY TIME position and adjust this control to
obtain a triggered delayed sweep. Rotate the DELAY TIME
MULT control to display the desired portion of the signal.
NOTE
in this mode of operation the displayed portion of
the signai will jump from line to line as the DELAY
TIME MUL Tcontrol is slowly rotated.
c. Disconnect the 10X probe.
6. Check Variable Line Selector Operation
a. Apply the desired composite video signal to the
vertical plug-in unit.
b. Check that the 7B53A/7B53AN OPTION 5 Main
Triggering Amplifier SOURCE switch is set to TV FIELD
and the TIME/DIV switch is set to 2 ms. Set the TIME/DIV
VARIABLE control to display slightly less than two fields.
Adjust the Main Triggering LEVEL control to obtain a
triggered display.
c. Set the 7B53A/7B53AN OPTION 5 DLY'D TRIG
control to RUNS AFTER DLY TIME position. Set the
Delayed Sweep Triggering controls as follows:
SLOPE
COUPLING
DC
SOURCE TV LINE
8. Check Main Triggering Amplifier TV Line Oper­
ation
a. Set the TIME/DIV to 10 µs. Check that the Main
Triggering Amplifier SOURCE switch is set to TV LINE.
b. Adjust the Main Triggering Amplifier LEVEL control
to obtain a stable display at H rate.
9. Check Delayed Internal Trigger Operation
Move the coaxial cable connector from P903 to P904 on
the TV sync separator board and change the Delayed Sweep
Triggering SOURCE TV LINE pushbutton. The INT/EXT
pushbutton is stored inside the 7B53A/7B53AN OPTION 5
plug-in unit on the TV Sync Separator board.
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