•The purpose of a trigger signal is to be sure
that the measurement made is made
on an appropriate signal not noise or an unwanted signal
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•Frequently we use larger rather than smaller signal –
example include light scatter
or fluorescence
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•The key component is called the comparator circuit which is designed around an analog and a digital input.
•
•The circuit is designed to have a constant voltage (set
by the operator) and a signal
from the sample – by comparing the preset signal with the sample signal, a cell is collected if it
meets the criterion (digital
signal is 1, or rejected (digital signal is 0).
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•Noise of no cells passing through the observation point
means that the comparator circuit
output is a logical - so no signal is collected or passed onto the rest of the detection circuit (this
means the computer does not have
to waste valuable time)
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