HP 54645A User's And Service Manual page 181

Using Option 005 Enhanced TV/Video Trigger (HP 54645A)
To trigger on a specific line of video
Figure 6-1
Triggering on Line 71
Note the TV Grid displayed (selected from the Display menu).
Table 6-1 Line Numbers per Field for Each TV Standard
TV Standard
NTSC
PAL
SECAM
GENERIC
6-6
Field 1
1 to 263
1 to 313
1 to 313
1 to 1024
Line Number Represents Count
In GENERIC mode, the line number represents the number of a count instead of
a real line number. This is reflected in the label above the softkey changing from
Line to Cnt. In the Trigger On selections, Field 1, Field 2 and Vertical are used to
indicate where the counting starts. For an interlaced TV system, the counting
starts from the rising edge of the first vertical serration pulse of Field 1 and/or
Field 2. For a non-interlaced TV system, the counting starts after the rising edge
of the vertical sync pulse.
Field 2 Alt Fld
1 to 262 1 to 262
314 to 625 1 to 313
314 to 625 1 to 313
1 to 1024 1 to 1024 (Vertical)