Scientific SMO1000E, User Manual

Page: 64 / 185

Scientific
SMO1000E 64/185
Trigger Source
The oscilloscope’s trigger source includes analog channels ( CH1 , CH2 ), EXT , EXT/5 and
AC Line .
Press the Setup button on the front panel to enter the TRIGGER function menu; press the
Source softkey and then turn the Universal Knob to select the desired trigger source.
The current trigger source is displayed at the upper right corner of the screen. Select
channel with signal input as trigger source to obtain stable trigger.
Analog channel input:
Signals input from analog channels CH1 and CH2 can all be used as the trigger source.
No matter whether the input of the channel selected is enabled, the channel can work
normally.
External trigger input:
External trigger source can be used to connect external trigger signal to the EXT TRIG
channel when all of the four channels are sampling data. The trigger signal (such as
external clock and signal of the circuit to be tested) will be connected to EXT and EXT/5
trigger source via the [EXT TRIG] connector. EXT/5 trigger source attenuates the
signal by a factor of 5. It extends the trigger level. You can set the trigger condition
within the range of trigger level (-8 div to +8 div).
AC line:
The trigger signal is obtained from the AC power input of the oscilloscope. This kind of
signals can be used to display the relationship between signal (such as illuminating
device) and power (power supply device). For example, it is mainly used in related
measurement of the power industry to stably trigger the waveform output from the
transformer of a transformer substation.
Note: to select stable channel waveform as the trigger source to stabilize the display.