Tektronix 7B53A, Инструкция по эксплуатации

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7B53A/7B53AN OPTION 5
OPERATING INSTRUCTIONS
Introduction
This section describes using the TV Sync Separator
portion of the time base plug-in unit.
Using the TV Sync Separator Plug-In
a. Connect a coaxial cable from the oscilloscope vertical
signal input connector to a composite video signal source of
such amplitude as to produce at least 2 major divisions of
vertical deflection.
Set the 7B53A/7B53AN OPTION 5 controls as follows:
Main Triggering Amplifier
SLOPE
MODE
COUPLING
SOURCE
AUTO
DC
TV FIELD
TIME/DIV
MAG
Main Time Base
2 ms
X1
b. Set the oscilloscope Main Triggering Amplifier
SOURCE switch to TV FIELD and the SLOPE switch to —.
c. Refer to the information under Obtaining a Display
in this section to obtain a display.
Adjusting the CLIPPING LEVEL Control (R914)
NOTE
If the input amplitude of the composite video
changes, it may be necessary to readjust the CLIP­
PING LEVEL control (R914).
a. Connect the composite video as described under the
heading Using the TV Sync Separator Plug-In.
b. Turn the CLIPPING LEVEL control (R914) fully
clockwise.
c. Set the oscilloscope controls to obtain the desired
video display.
d. Slowly rotate the CLIPPING LEVEL control (R914)
counterclockwise until a point is found where the most
stable video display results.
TWO FIELD DISPLAY
To obtain a two field display, adjust the LEVEL control
to obtain a triggered display. The TIME/DIV VARIABLE
control may be adjusted to obtain a display of slightly less
than two fields.
LINE DISPLAYS
1.
Variable Line Selector. To obtain Variable Line
Selector capabilities, the DLY'D TRIG control must be set
to the RUNS AFTER DLY TIME position. Pull the
TIME/DIV knob outward and rotate the knob to the
desired time/div position (10 µs). Rotate the DELAY TIME
MULT control to the desired portion of the waveform.
Push the TIME/DIV knob in and the desired portion of the
waveform will be displayed. The delayed sweep is free
running in this mode of operation.
2. Discrete Line Selector. For Discrete Line Selector
capability, place the Delayed Sweep Triggering SOURCE
switch in TV LINE position. Rotate the DLY'D TRIG
control out of the RUNS AFTER DLY TIME position and
set the control to obtain a triggered sweep. Rotate the
DELAY TIME MULT control until the desired line is
displayed. When rotating the DELAY TIME MULT control,
the display will jump from line to line.
3. Main Triggering Amplifier TV Line. Set the TIME/
DIV switch to 10 µs and check that the Main Triggering
Amplifier SOURCE switch is set to TV LINE. Adjust the
LEVEL control to obtain a stable display at the H rate.
Obtaining a Display
Install the TV Sync Separator Plug-In in the oscilloscope
as described under Using the TV Sync Separator. The
following instructions apply for the 7B53A/7B53AN OP­
TION 5 plug-in unit.
DELAYED INTERNAL TRIGGER OPTION
The Delayed Sweep Triggering SOURCE selection may
be changed from TV LINE/EXT to INT/EXT or vice versa.
For INT/EXT triggering source capability, move the coaxial
connector from P903 to P904 and change the pushbutton
to read INT/EXT. The pushbutton is stored on the TV
Sync Separator board.
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