Trigger Source
The Trigger SOURCE switch allows for selectivity in determining
the source to trigger the sweep. For most applications, the sweep
can be triggered internally. In the COMP position, the trigger signal
is obtained from the vertical deflection system after the vertical
switching has occurred. Therefore, in the dual-trace mode of
operation, the display will be triggered on the chopping signal and
not necessarily on the selected slope of the LEVEL/SLOPE control.
In this position the 212 will trigger on at least 0.2 division of the
applied signal within the bandwidth limits of the instrument.
In the CH 2 position of the Trigger SOURCE switch, the trigger
signal is again obtained internally, but is selected before the vertical
switching and only from CH 2 of the vertical deflection system, on at
least 0.2 division of the applied capacitively coupled signal. In the
dual-trace mode, if the displayed signals are time related, both
channels can be triggered on the selected slope with the Trigger
SOURCE switch in this position. However, it is not necessary for
the CH 2 POSition control to be out of the OFF detent for a trigger
to be present in the CH 2 position.
17
212 Operators Handbook
