Tektronix CSA7404B, User Manual

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Triggering
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CSA7000B Series & TDS7000B Series Instruments User Manual
Overview Control elements and resources Triggering from the front panel (Cont.)
To set to 50% 5. To quickly obtain an edge, glitch, timeout, serial, or
width trigger, push the trigger LEVEL knob. The
instrument sets the trigger level to the halfway point
between the peaks of the trigger signal. This function
has no effect for the other advanced trigger types.
You can also set the level to 50% in the Trigger control
window.
When the phased locked loop is active (Comm and
Serial Trigger only which are optional on the TDS7000B
Series), pushing the trigger LEVEL knob recycles the
clock-recovery trigger circuit. The instrument will attempt
to acquire lock once. If the input data is disrupted,
removed, or heavily distorted, the instrument may not
acquire lock or may lose lock. If the recovered clock is
not locked to the incoming data, the waveform display
will not be stable. Once the input data is available, press
the PUSH SET TO 50% knob to force the instrument to
reacquire lock.
When using Comm triggering, pushing the trigger PUSH
SET TO 50% knob sets the levels for the selected code.
To select the
trigger source
6. Push the up and down arrow buttons to toggle through
the possible trigger sources:
H
CH 1 - CH 4 are the input channels. The channel
you select as a trigger source will function whether
it is displayed or not.
H
LINE is the AC Line Voltage. Because the
instrument generates the trigger, you do not have to
input a signal to create the trigger.
H
AUX is a fifth, nondisplayable trigger source. To
use the auxiliary trigger, connect the external
triggering signal to the Auxiliary Trigger input
connector on the front panel.