138 Agilent InfiniiVision 2000 X-Series Oscilloscopes User's Guide
10 Trigger Mode/Coupling
• "To position the time reference (left, center, right)" on page 52
To select the trigger coupling
1 Press the [Mode/Coupling] key.
2 In the Trigger Mode and Coupling Menu, press the Coupling softkey;
then, turn the Entry knob to select:
• DC coupling — allows DC and AC signals into the trigger path.
• AC coupling — places a 10 Hz high-pass filter in the trigger path
removing any DC offset voltage from the trigger waveform.
The high- pass filter in the External Trigger input path is 50 Hz for
all models.
Use AC coupling to get a stable edge trigger when your waveform has
a large DC offset.
• LF (low frequency) Reject coupling — adds a high- pass filter with the
3- dB point at 50 kHz in series with the trigger waveform.
Low frequency reject removes any unwanted low frequency
components from a trigger waveform, such as power line frequencies,
etc., that can interfere with proper triggering.
Use LF Reject coupling to get a stable edge trigger when your
waveform has low frequency noise.
• TV coupling — is normally grayed- out, but is automatically selected
when TV trigger is enabled in the Trigger Menu.
Pass
Band
50 kHz
0 dB
3 dB down point
DC