OPHIR vega User Manual page 73

Then the user can choose to measure a number of pulses
and display only the average.
To set up for averaging over a number of pulses:
1. From the main measurement screen, select "Menu"
and enter. Select "Configure" and enter.
2. Now select "Average" and enter. Select the time
period you wish to average over and enter. If you do
not want to average, but collect individual pulses
then select "NONE".
3. If you wish to save the new setting as the default,
press "Save" before enter.
Note:
The Pyroelectric sensor is capable of measuring
pulses up to very high repetition rates on the order of
kilohertz or higher. The Vega actually captures each
pulse up to 4000Hz and will sample pulses at up to
25,000 pulses depending on the sensor. The pulses
collected can be stored for later recovery and
transmission. (See section 4.4.2.6.1). However, the
display can only display at rates up to 10Hz. At higher
rates, if the user has chosen "NONE", the Vega will
display individual pulses
sampled at a rate of 5Hz. If the user has chosen to
average over a time period,
display the average of readings over the period from
the time the screen was entered up to the present. For
instance, if the average period is 30 seconds, at 15
seconds, the average is over 15 s., at 30 seconds it is
over 30 seconds, at 5 minutes, it is over the period
from 4.5 to 5 minutes (30 seconds back from the
present etc.).
6.2.2.3 Setting the Threshold (PE-C sensors)
Pyroelectric sensors are sensitive to noise and vibration
as well as the heat from the laser pulses. They can falsely
trigger on such disturbances, especially on the lowest
ranges. The PE-C series of sensors has a user settable
threshold to suppress such false triggering. The default
the instrument will
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