Tektronix 222PS, Operator'S Manual

Page: 115 / 232

Triggering
222PS Operator Manual
3Ć69
Trigger Coupling
In the 222PS, the coupling of the trigger source is the same as the
coupling of the channel it is using. An external trigger is always DCĆ
coupled.
Trigger Slope
To determine the trigger slope presently in use, look at the bottom
readouts. At the left is the trigger level in volts. Immediately to its right
is the trigger slope indicator. A plus ( + ) indicates a positive slope; a
minus ( - ) indicates a negative slope.
To change the trigger slope, press the SLOPE button in the frontĆ
panel trigger controls. This button toggles between positive and
negative slopes.
Trigger Level
The trigger level presently in use appears at two places on the screen.
It appears as a small + on the screen at the trigger position. Its value
in volts is the leftmost of the bottom readouts.
You can set the trigger level of the 222PS anywhere within the vertical
range of the instrument. The signal used for triggering need not
appear on the screen. If the trigger level is off the screen and the
instrument is triggered, the + trigger level indicator is at the top or the
bottom of the screen, indicating the direction of the trigger level.
To set the trigger level explicitly, follow these steps.
ĂĂStep 1:ă Ensure that the trigger mode is normal, auto baseline, or
single sequence. (In auto level mode, the 222PS sets the trigger
level automatically. Trigger modes are discussed on page 3Ć71.)
ĂĂStep 2:ă Turn the TRIGGER LEVEL knob located in the left side of
the trigger control area. Turning the outer knob clockwise raises
the trigger level; turning it counterclockwise lowers the trigger
level.
Triggering
222PS Operator Manual
3Ć69
Trigger Coupling
In the 222PS, the coupling of the trigger source is the same as the
coupling of the channel it is using. An external trigger is always DCĆ
coupled.
Trigger Slope
To determine the trigger slope presently in use, look at the bottom
readouts. At the left is the trigger level in volts. Immediately to its right
is the trigger slope indicator. A plus ( + ) indicates a positive slope; a
minus ( - ) indicates a negative slope.
To change the trigger slope, press the SLOPE button in the frontĆ
panel trigger controls. This button toggles between positive and
negative slopes.
Trigger Level
The trigger level presently in use appears at two places on the screen.
It appears as a small + on the screen at the trigger position. Its value
in volts is the leftmost of the bottom readouts.
You can set the trigger level of the 222PS anywhere within the vertical
range of the instrument. The signal used for triggering need not
appear on the screen. If the trigger level is off the screen and the
instrument is triggered, the + trigger level indicator is at the top or the
bottom of the screen, indicating the direction of the trigger level.
To set the trigger level explicitly, follow these steps.
ĂĂStep 1:ă Ensure that the trigger mode is normal, auto baseline, or
single sequence. (In auto level mode, the 222PS sets the trigger
level automatically. Trigger modes are discussed on page 3Ć71.)
ĂĂStep 2:ă Turn the TRIGGER LEVEL knob located in the left side of
the trigger control area. Turning the outer knob clockwise raises
the trigger level; turning it counterclockwise lowers the trigger
level.