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[2] MAGNIFIED SWEEP OPERATION
Sfnce merely shortening the s w e e p time to magnify a portion of an observed w a v e f o r m
can result in the desired portion disappearing off the screen, such magnified display should
be performed using the MAGNIFIED S W E E P .
Using the
POSITION control, adjust the desired portion of w a v e f o r m to the C R T . Pull
out the PULL x 5 M A G control to magnify the display 5 times. For this type of display the
s w e e p time is the S W E E P T I M E / D I V setting divided by 5 .
[3] X - Y OPERATION
For some measurements, an external horizontal deflection signal is required. T h i s is also
referred to a s an X - Y measurement, where the Y input provides vertical deflection and
X input provides horizontal deflection.
X - Y operation permits the oscilloscope to perform many types of measurements not pos-
sible with conventional s w e e p operation. T h e C R T display becomes an electronic graph
of t w o instantaneous voltages. T h e display may be a direct camparison of t w o voltages
s u c h a s during phase measurement, frequency measurement with Lissajous w a v e f o r m s .
To use an external horizontal input, use the following procedure;
1. Set the S W E E P T I M E / D I V control to the X - Y position.
2. Use the channel 1 probe for the vertical input and the channel 2 probe for the horizon-
tal input.
3 . Adjust the amount of horizontal deflection w i t h the C H 2 V O L T S / D I V and V A R I A B L E
controls.
4 . T h e C H 2 (vertical) POSITION (§) control now serves as the horizontal position control,
and the ^ POSITION control is disabled.
5 . All s y n c controls are disconnected and have no effect.
[4] VIDEO SIGNAL OBSERVATION
The T V - V / H s w i t c h permits selection of vertical or horizontal s y n c pulse for s w e e p trig-
gering w h e n viewing composite video w a v e f o r m s . In the T V - H position, horizontal s y n c
pulses are selected as triggers to permit viewing of horizontal line of video. T h i s is also
the position used for viewing all non-video w a v e f o r m s . In the T V - V position, vertical s y n c
pulses are selected as triggers to permit viewing of vertical fields and frames of video.
W h e n observing the video w a v e f o r m s , stable display is obtained on the screen regardless
the T R I G L E V E L @ control.
A t most points of measurement, a composite video signal is of the polarity, that i s , the
s y n c pulses are negative and the video is positive. In this c a s e , use " - "
If the waveform is taken at a circuit point where the video w a v e f o r m is inverted, the s y n c
pulses are positive and the video is negative. In this c a s e , use " + " S L O P E .
S L O P E .
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