LeCroy Digital Oscilloscopes, Manual

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Coupling refers to the type of signal coupling at the input to the
trigger circuit. The trigger coupling can be selected independently
from the following options:
À
DC: All the signal’s frequency components are coupled to the
trigger circuit for high-frequency bursts or where the use of AC
coupling would shift the effective trigger level.
À
AC: The signal is capacitively coupled, DC levels are rejected
and frequencies below 50 Hz attenuated (< 10 Hz for the
LC564
AND
LC584 S
ERIES
).
À
LF REJ: The signal is coupled via a capacitive high-pass filter
network, DC is rejected and signal frequencies below 50 kHz are
attenuated (< 100 MHz for the
LC564
AND
LC584 S
ERIES
). For
stable triggering on medium- to high-frequency signals.
À
HF REJ: Signals are DC-coupled to the trigger circuit and a low-
pass filter network attenuates frequencies above 50 kHz. For
triggering on low frequencies.
À
HF: To be used only when necessary for triggering on high-
frequency repetitive signals > 300 MHz, with a maximum trigger
frequency of > 500 MHz (> 1 GHz for the
LC564
AND
LC584
S
ERIES
). HF is automatically overridden and set to AC when
incompatible with other trigger characteristics (and SMART
triggers). Only one slope available.
67(3
Press the corresponding menu to select “
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”. The
screen will display as shown next page: