HP 16533A, User Reference, Page: 71 / 152

Level Field
The Level field shows the trigger level voltage value. When the voltage value
on the trigger source equals the trigger level, the oscilloscope triggers. The
point at which the oscilloscope triggers is called the trigger point (see the
illustration below). The trigger point is shown on the screen as a vertical
dotted red line, called the trigger marker. At zero delay time, the trigger
marker is located at the horizontal center of the screen. At delay time T
d
, the
trigger point is offset left (positive delay) or right (negative delay) from the
horizontal center of the screen by time T
d
.
When you change the trigger level voltage value, the waveform moves
horizontally on the display to maintain the trigger point. (That is, the point
where the waveform voltage value equals the trigger point voltage value.)
This is illustrated below.
The Trigger Menu
Level Field
6-7