6-3
IM 701510-01E
Activating a
T
rigger
6
EXT (external Trigger)
Select this when connecting the trigger signal source to the “EXT TRIG IN/EXT CLOCK
IN” terminal on the rear panel (also used as the terminal for an external clock) and selecting
the signal as the trigger source.
For DL1520/DL1520L, connect the trigger signal source to the “EXT TRIG” terminal on
the front panel.
For the specifications of the terminal, refer to “When “EXT IN” is selected” in section 5.7
CAUTION
If a clock signal exceeding the above permissible maximum input voltage is
input to the each terminal, damage to the internal circuits of the instrument
may result.
The trigger slope must be selected from “
”, “
” and “
” in the same way when one
of the channels CH1 to CH4 (for DL1520/DL1520L, CH1/CH2) is selected. For DL1540/
DL1540L, the trigger level must be either “0.15 V” or “1.5 V”.
• Setting the EXT range (for DL1520/DL1520L)
Select either
±
1 V or
±
10 V range. The default is
±
10 V range.
• Setting the attenuation for EXT probe (for DL1520/DL1520L)
Select 1:1, 10:1, 100:1 or 1000:1. The default is 10:1.
• Setting the EXT trigger level (for DL1520/DL1520L)
The EXT trigger level can be set within the following range. This range is effective if the
probe’s attenuation is set to 1:1. If the probe’s attenuation is set to10:1, 100:1 or 1000:1,
the range will be multiplied by10, 100 and 1000 respectively.
• EXT range is
±
1 V: –1 V to +1 V in steps of 4 mV
• EXT range is
±
10 V: –10 V to +10 V in steps of 40 mV
* For DL1540/DL1540L, refer to “EXT (external Trigger)” on this page.
LINE (Line trigger)
Select this when the signal to be displayed is synchronized with the frequency of the
commercial power source (50 Hz /60 Hz) and you want to select the commercial power
source voltage signal as the trigger source signal.
Points to note when setting the edge trigger
• If the trigger type setting is changed, the edge trigger setting will be invalidated.
However, selecting the edge trigger will restore the previous edge trigger setting.
• If the trigger mode is not auto-level mode, the trigger level will not change once it has
been set. Thus, changing the amplitude of the trigger signal or changing the offset may
invalidate the trigger level, thereby hindering activation of a trigger. Conversely, if the
trigger mode is auto-level mode, the median of the amplitude of the trigger signal is
detected and the trigger level is set to the median value automatically if the trigger level
is invalidated. For a detailed description, refer to 6.8 “Setting the Trigger Mode” (page 6-
12).
Note
If the trigger slope is set to “up/down
”, no trigger can be activated either at “rise
” or “fall
”.
In this case, try to set an appropriate hold-off time. This may cause a trigger to be activated. For a
description of how to set the hold-off time, refer to page 6-19.
6.2 Setting the Edge Trigger
