5-8
Making Measurements
To reduce the random noise on a signal
3 Use averaging to reduce noise on the displayed waveform.
•Press the Acquire key, then press the Averaging softkey.
Averaging lets you average multiple triggers together to reduce noise and
increase resolution. Averaging of multiple triggers requires a stable trigger.
The number of triggers being averaged is displayed in the # Avgs softkey.
Turn the Entry knob to set the numb er of averages (# Avgs) that best
eliminates the noise from the displayed wav eform.
The number of averages can be set from 1 to 16383 in increments of powers
of 2. The higher the number of averages you set, th e more noise reduction
and resolution that will be accomplished.
When th e n um ber of av er age s i s h igh er , mo re no is e is re mo ve d fr om th e d isp la y.
How e ve r, t he h ig h er th e n um be r o f a ve r ag e s, t he s lo w er t he d is p la y ed w av e fo r m
responds to waveform changes. You must compromise between how quickly
the waveform responds to changes and how much you want to reduce the
displayed noise on the signal.
128 Averages used to reduce noise
# Avgs Bits of resolution
18
49
16 10
64 11
256 12