Tektronix TPS2012B, Руководство пользователя

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Reference
Video Trigger
Options Settings Comments
Video With Video highlighted, triggering
occurs on an NTSC, PAL, or SECAM
standard video signal
Trigger coupling is preset to AC
Source Channel 1, 2, 3 1 , or 4 1 ,
Ext, Ext/5, Ext/10
Selects the input source as the
trigger signal; Ext, Ext/5, and
Ext/10 selections use the signal
applied to the Ext Trig connector
Polarity Normal, Inverted Normal triggers on the negative edge
of the sync pulse; Inverted triggers on
the positive edge of the sync pulse
Sync All Lines, Line Number,
Odd Field, Even Field, All
Fields Select an appropriate video sync
Use the multipurpose knob to specify
a line number when you select Line
Number for the Sync option
Standard NTSC, PAL/SECAM Select the video standard for sync
and line number count
1
Available only on a 4-channel oscilloscope.
Key Points
Sync Pulses. When you choose Normal Polarity, the trigger always occurs on
negative-going sync pulses. If your video signal has positive-going sync pulses,
use the Inverted Polarity selection.
Pulse Width Trigger
Use Pulse Width triggering to trigger on normal or aberrant pulses.
Options Settings Comments
Pulse With Pulse highlighted, triggering
occurs on pulses that meet the trigger
condition de
fi ned by the Source,
When, and Set Pulse Width options
Source Channel 1, 2, 3 1 , or 4 1 ,
Ext, Ext/5, Ext/10
Select the input source as the trigger
signal
When =, ≠ , <, > Select how to compare the trigger
pulse relative to the value selected in
the Pulse Width option
Pulse Width 33 ns to 10.0 sec Use the multipurpose knob to set a
width
Polarity Positive, Negative
Select to trigger on positive or
negative pulses
Mode Auto, Normal Select the type of triggering; Normal
mode is best for most Pulse Width
trigger applications
TPS2000B Series Digital Oscilloscope User Manual 115