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SLOPE " - " RANGE
SLOPE " + " RANGE.
Fig. 9
*
A u t o Trigger
When the TRIG MODE
@) selection is in AUTO, the
sweep circuit becomes free-running as long as there is no
trigger signal, permitting a check of GND level. When a trig-
ger signal is present, the trigger point can be determined by
the LEVEL control for observation as in the normal trigger
signal. When the trigger level exceeds the limit, the trigger
circuit also becomes free-running where the waveform
starts running. When the LEVEL control is pushed in and/or,
when the trigger signal is absent or the triggering level ex-
ceeds the limit, there is no sweep.
(2) M A G N I F I E D SWEEP OPERATION
Since merely shortening the sweep time t o magnify a por-
tion of an observed waveform can result in the desired por-
tion disappearing off the screen, such magnified display
should be performed using the MAGNIFIED SWEEP.
Using the
POSITION control, adjust the desired portion
of waveform t o the CRT. Pull out the PULLx 10 MAG con-
trol t o magnify the display 10 times. For this type of
display the sweep time is the SWEEP TIME/DIV setting
divided by 10.
(3) X - Y OPERATION
For some measurements, an external horizontal deflection
signal is required. This is also referred t o 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 w i t h conventional
sweep operation. The CRT display becomes an electronic
graph of t w o instantaneous voltages. The display may be a
direct camparison of t w o voltages such as during phase
measurement,
frequency
waveforms.
To use an external horizontal input, use the following pro-
cedure;
1. Set the TRIG MODE switch t o X-Y the 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 w i t h the CH2
VOLTS/DIV and VARIABLE controls.
4 . The <P- (horizontal) POSITION @
as the horizontal position control, and the CH2 • POSI-
TION control is disabled.
5. All sync controls are disconnected and have no effect.
16
LEVEL
measurement
w i t h
Lissajous
control now serves
(4) VIDEO S I G N A L O B S E R V A T I O N
The TV FRAME/LINE switch permits selection of vertical or
horizontal sync pulse for sweep triggering when viewing
composite video waveforms. In the LINE position, horizon-
tal sync pulses are selected as triggers t o permit viewing of
horizontal line of video. This is also the position used for
viewing all non-video waveforms. In the FRAME position,
vertical sync pulses are selected as triggers t o permit view-
ing of vertical fields and frames of video. When observing
the video waveforms, stable display is obtained on the
screen regardless the TRIG LEVEL @) control.
A t 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.
(5) SINGLE SWEEP (for t h e C S - 1 0 4 4 only)
Single sweep is used typically t o sweep a nonperiodic
waveform once only.
1. Set the TRIG MODE switch @) t o AUTO or NORM. For
use as trigger input, connect a signal of practically the
same amplitude and frequency as the signal to be
displayed. Then set a trigger level.
2. Set the TRIG MODE switch @> t o REST. The LED label-
ed " R E A D Y " will go on, indicating the trigger wait
state. The LED will go off upon completion of A sweep.
3. Being sure that the " R E A D Y " LED is lit, connect the
signal to be observed, and set the TRIGE MODE control
@> t o REST so that the unit is waiting for trigger. Once
the signal is triggered, it will be swept once and the
" R E A D Y " LED will go off.
NOTE: Dual trace waveform cannot be observed if the
vertical MODE is set t o ALT. Use the CHOP mode
instead.
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