Elenco 30MHz Dual Trace - Manual (Page 47)

44
OPERATING INSTRUCTIONS
HOLD OFF Control
Controls hold-off time between sweep signals to obtain stable display when
triggering a periodic signal. The control hold time ranges from 1 to 5 times time base.
Refer to Fig.3(A): shows a case for HOLD OFF knob at the NORM position. Various
different waveforms are overlapped on the screen, making the signal observation
unsuccessful.
Refer to Fig.3(B): show a case in witch the undesirable portion of the signal is held
off.
The same waveforms are displayed on the screen without overlapping.
In such a case, the sweep can be stable synchronized to the HOLD OFF time (sweep
pause time) of the sweep waveform.
TIME BASE Control
1. Sweep TIME/DIV Control
Set the sweep TIME/DIV control to display the desired number of cycles of the
waveform. If there are too many cycles displayed for good resolution, switch to
faster sweep time. If only a line is displayed, try a slower sweep time. When the
sweep time is faster than the waveform being observed, only part of it will be
displayed, which may appear as a straight line for a square wave or pulse
waveform.
Adjusting
the HOLD OFF
time
Sweep
Waveform
A complex waveform
(Digital signal)
Cycle
Heavy parts are display
Fig.3
(A)
(B)