GW Instek GOS-6000 Series - Manual (Page 23)

GOS-6051/6050/6031/6030 OSCILLOSCOPE
USER MANUAL
⎯ 40 ⎯
Operating Hold off time Control
When the measured signal is a complex waveform with two or more repetition
frequencies (period), triggering with the LEVEL control alone may not be
sufficient to attain a stable waveform display. In such a case, the sweep can be
stable synchronized to the measured signal waveform by adjusting the Hold
off time of the sweep waveform.
Figure 5-10(a) shows several different waveforms which overlapped on the
screen, marking the signal observation unsuccessful when the hold off is set to
minimum.
Figure 5-10(b) shows the undesirable portion of the signal is held off. The
same waveforms are displayed on the screen without overlapping.
Figure 5-10(a)
Figure 5-10(b)
GOS-6051/6050/6031/6030 OSCILLOSCOPE
USER MANUAL
⎯ 41 ⎯
Observing the Synchronization of two Waveforms
When two signals of the CH1 and CH2 have the same frequencies with an
integral number, or a specific time difference, the SOURCE selects either CH1
or CH2 as a reference signal. Select CH1 signal from CH1 position and select
CH2 signal from CH2 position as a reference.
Set the SOURCE to VERT-MODE for observing the signal of different
frequencies. Switch the sync signal alternately to each channel, the waveform
of each channel will be triggered stably.
When set the SOURCE to VERT-MODE and set the ALT/CHOP to ALT, the
input signals applied to CH1 and CH2 will become trigger source alternately
during sweep. Consequently, even the waveforms of different frequency of
each channel can be triggered stably.
Apply a sine wave to CH1 and a square wave to CH2, “A”s shown in Figure 5-
11 are at the level possible for synchronization.
Figure 5-11 Trig. Source on VERT
Apply AC coupling to CH2 in order to expand the synchronization range.
If the input signal of CH1 or CH2 becomes small, adjust VOLT/DIV control
knob to obtain sufficient amplitude.
The VERT-MODE triggering required 2.0 div which is larger than the
amplitude of CH1 or CH2.