Connection To Signal Source; Basic Setup - Pyramid D100 User Manual

PSI System Controls and Diagnostics

8.3 Connection to signal source

8.3.1 Basic setup

Figure 3 shows a typical installation for a single sodium iodide / photomultiplier in schematic
form.
HV PSU
HV
HV control
Comms
A500
D100
NaI Photomultiplier Base
Signal
Data stream
Pulser LED Temperature sense and pulser
+24V in
Figure 3. Schematic D100 installation
The fiber-optic communication channel is a looped system. Up to 15 devices, which could all be
D100s, or a mix of various devices) can be connected to a host computer via the A100, A200 or
A300 interfaces.
CAUTION. The D100 has a DC-coupled input, and thus must not be used with
photomultipliers that have the signal sitting on a high-voltage. Connecting the D100 input to a
high voltage will result in serious damage and will void warranty.
The D100 is optimized for DC-coupling direct to the anode. AC-coupled operation, with a
blocking capacitor in the photomultiplier base, is also possible, albeit with some degradation in
spectrometry performance. Contact your supplier or Pyramid Technical Consultants, Inc. for
information about firmware updates to optimize performance in AC-coupled systems. If you are
in any doubt about the suitability of your photomultiplier, please consult your supplier or
Pyramid Technical Consultants, Inc. before attempting to use the D100.
If you are using a photomuliplier, the base must not include a pre-amplifier, because the D100 is
designed to receive the anode current pulses directly. The high voltage supply may be external
or integrated with the base. The dynode voltage division may be resistive or active.
D100 User Manual D100_UM_081027 Page 16 of 46