Source Field - HP 1660CS-Series User Manual

The Scope Trigger Menu

Source field

of 2 mV (V/Div = 100 mV x 4 x 0.005 = 2 mV). Values entered that are not in
this range will be rounded to the nearest 0.05% increment.
Since the trigger level range is limited by the voltage values displayed in the
waveform window, the voltage window limits can be easily determined. Turn
the knob in both directions until the Level field reads minimum and
maximum voltage. These voltage values are the limits of the waveform
window. However, if the level is set at the min or max of a window and offset
for that channel is changed, the trigger level will track that change, thereby
changing the window limits.
If the trigger source channel is displayed in the waveform area of the screen,
the trigger level marker will appear on the screen as a horizontal dashed line.
The trigger level marker will move up and down on the screen as the trigger
level voltage is changed.
If the trigger source channel is not in the waveform area of the screen, the
trigger level marker will not be displayed.
If there are multiple occurrences of the trigger source waveform in the
waveform area of the screen, only the uppermost occurrence of the trigger
source waveform will display the trigger source marker.
The trigger level marker only appears when the trigger menu is selected.
The default value for the Level field is 1.620 V (TTL preset value).
Source field
When you select the Source field, a pop-up menu appears showing the inputs
available as the trigger source. The source can be channel 1 or channel 2.
At power-up, the default channel input selection for the Source field is the
lowest numbered input channel. For example, if inputs are connected to
both channels 1 and 2, the Source field defaults to 1. However, if an input
signal is only connected to channel 2, the Source field defaults to 2 when you
automatically scale with Autoscale, even though channel 1 is the default at
power-up.
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