Owner`s manual

20
Trigger Source — A trigger source selection deter-
mines how a received pulse or signal is to be monitored
or measured. The five selectable trigger sources are:
AUTO
: The ProbeScope continuously measures
and records signals each time a trigger occurs re-
gardless of its level (higher, lower, or equal to the
incoming signal). If you set the input coupling
switch to
GND
, the ProbeScope automatically sets
the trigger to
AUTO
.
+
INTERN
: The ProbeScope records signals only
when the defined trigger event occurs. The signal
is recorded when the trigger level is equal to the in-
coming signal and the signal is rising.
–
INTERN
: The ProbeScope records signals only
when the defined trigger event occurs. The signal
is recorded when the trigger level is equal to the in-
coming signal and the signal is falling.
Note: The maximum and minimum voltage levels
of the + or – internal trigger depends on the
Input
Volta
g
e
Selector
+
EXTERN
: The ProbeScope records signals only
when the defined trigger event occurs. The signal
is recorded when the trigger level is equal to the
signal present at the external trigger plug and the
signal is rising.
–
EXTERN
: The ProbeScope records signals only
when the defined trigger event occurs. The signal
is recorded when the trigger level is equal to the
signal present at the external trigger plug and the
signal is falling.
0
0.1
0.3
0.5
-0.1
-0.3
-0.5
0
1
3
5
-1
-3
-5
0
10
30
50
-10
-30
-50
1 V 10 V 100 V
22-310.fm Page 20 Friday, August 6, 1999 12:26 PM