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Note that for this type of operation both the DELAY TIME
MULT and trigger LEVEL controls affect the start of the B
sweep so that the delay time is used as a reference point.
(4) X-Y OPERATION
For some measurements, an external horizontal deflection
signal is required. This is also referred to as an X - Y
measurement, where the Y input provides vertical deflec-
tion and X input provides horizontal deflection.
X-Y operation permits the oscilloscope to perform many
types of measurements not possible with conventional
sweep operation. The C R T display becomes an electronic
graph of two instantaneous voltages. The display may be a
direct comparison of two voltages such as during phase
measurement, or frequency measurement with Lissajous
waveforms.
To use an external horizontal input, use the following pro-
cedure;
1. Select the HORIZ DISPLAY switch to X - Y position.
2. Use the channel 1 probe for the vertical input and the
channel 2 probe for the horizontal input.
3. Adjust the amount of horizontal deflection with the
channel 2 VOLTS/DIV and VARIABLE controls.
4. The channel 2 (vertical) POSITION
serves as the horizontal position control, and the
POSITION control is disabled.
5. All sync controls are disconnected and have no effect.
X and Y axis sensitivities are set by using the channel 2
and channel 1 VARIABLE, VOLTS/DIV controls respec-
tively.
By pulling out the channel 1 and channel 2 VARIABLE
controls, the sensitivities of both the Y and X axis are
magnified five times. A INTENSITY control is used to ad-
just the intensity of the display during X - Y operation.
(5) VIDEO SIGNAL OBSERVATION
The A SWEEP TIME/DIV control permits selection of ver-
tical or horizontal sync pulse for sweep triggering when
viewing composite video waveforms. In the LINE position,
(50 jts/div to 20 ns/div) horizontal sync pulses are selected
as triggers to permit viewing of horizontal line of video. In
the FRAME (0.5 s/div to 0.1 ms/div) position, vertical
sync pulses are selected as triggers to permit viewing of
vertical fields and frames of video. When observing the
video waveforms, stable display is obtained on the screen
regardless the trigger LEVEL @
At most points of measurement, a composite video signal
is of the (—) polarity, that is, the sync pulses are negative
and the video is positive. In this case, use " —" SLOPE.
If the waveform is taken at a circuit point where the video
waveform is inverted, the sync pulses are positive and the
video is negative. In this case, use " + " SLOPE.
16
(Q) control now
control.
(6) SINGLE SWEEP OPERATION
This mode
of
display is useful for
synchronous or one time events.
Procedure:
1. Select the trigger MODE @> to either AUTO or NORM.
Apply a signal of approximately the same amplitude and
frequency as the signal that is to be observed as the trig-
ger signal and set the trigger level.
2. Select trigger MODE switch to RESET -
the READY indicator LED lights to indicate the reset con-
dition. This LED goes out when the A sweep period is
completed.
3. After the above set-up is completed the scope is ready
to operate in the SINGLE sweep mode of operation after
resetting the instrument using the RESET switch. Input
of the trigger signal results in one and only one sweep
and READY indicator LED goes out.
r— NOTE:
With the HORIZ DISPLAY set to ALT the simultaneous
observation of the A sweep and B sweep waveforms
at SINGLE sweep mode is not possible. For dual trace,
single sweep operation, vertical MODE must not be set
to ALT. Observation is not possible using ALT mode.
Set the scope to the CHOP mode in this case.
looking at
non-
observe that
,
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