Tektronix 2212

Trigger
® Trigger COUPLING Switch
With the COUPLING switch you select the method of cou-
pling the trigger SOURCE signal to the trigger circuit (NOISE
REJ, AC, LF REJ, HF REJ, or DC). The LED indicator for the
selected COUPLING lights.
- NOISE REJ (Noise Reject) - In the NOISE REJ position
all frequency components of the trigger input signal are
coupled to the trigger circuitry, but increases the peak-to-
peak signal amplitude that is required to produce a trigger
event."Noise" is displayed in the crt trigger readout field.
NOTE
NOISE REJ trigger coupling is useful for improving
stability when the trigger signal is accompanied by low-
level noise.
- AC - In the AC position, the trigger input signal is ca-
pacitively coupled to the trigger circuit, and the de com-
ponent is blocked. "AC" is displayed in the crt trigger
readout field.
NOTE
AC trigger coupling is useful for triggering on ac wave-
forms that have a large de offset.
- HF REJ (High Frequency Reject)- In the HF REJ coupling
position, the high-frequency components from the trigger
input signal (above 30 kHz), are attenuated. "HFrej" is
displayed in the crt trigger readout field.
NOTE
HF REJ trigger coupling is useful for providing a stable
display of low-frequency components of complex wave-
forms and eliminates high-frequency interference from
the trigger signal.
2212 User Manual
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