TSI Instruments SIZER 3321, User Manual

Page: 34 / 101

3-8 Model 3321 Aerodynamic Particle Sizer

Spectrometer
BNC Connectors
Three BNC connectors provide the following signals.
Analog Out
The Analog Out BNC connector provides a programmable analog signal
that can be sent to a strip chart recorder or other analog device. Refer to
Appendix C, "Using Serial Data Commands," for serial commands that
control the signal output.
Time of Flight
The Time of Flight BNC connector provides a digital signal corresponding
to the gated level of the raw analog time of flight signal for each particle.
Pulse Out
The Pulse Out BNC connector provides amplified raw signals from the
photodetector. This signal can be used with an oscilloscope, for example,
to examine secondary characteristics of the pulses.
I n t e r n a l C o m p o n e n t s
The location of the functional systems and electronics of the Model 3321
APS
™
spectrometer are shown in Figure 3-6 and include:

Digital PC board

Analog PC board

Sheath flow pump

Total flow pump

Filters

Power Supply

Optics

Detector PC board

Laser PC board

Power PC board
The only serviceable components of the Model 3321 APS
™
spectrometer
are the filters, which require routine maintenance (refer to Appendix A ). For
a general description of these components, refer to Chapter 3, “
Description
of the APS
TM
Spectrometer
.” For a more detailed description, refer to
Chapter 5,
“
Theory of Operation
.”