ST365 Radiation Counter Technical Manual
May 2020 – Revision 2.0
Spectrum Techniques, LLC
www.spectrumtechniques.com
Page 4 of 14
INTRODUCTION
The ST365 Radiation Counter combines many features into a single inexpensive instrument. We have expanded the
classic nuclear scaler design to not only include a preset time function, a digital rate-meter, a digitally controlled high
voltage supply, but now with computer interfacing via USB, LAN, and Wi-Fi Direct formats.
The ST365 includes BNC and MHV connectors, as well as a precision high voltage supply that is adjustable from 0 to
+1200 volts. This high voltage supply provides 0.2mA at 1200 volts making it suitable for many types of Geiger
Mueller (GM) tubes and scintillation detectors.
The preset time function enables the user to acquire radioactive events for a predetermined number of seconds. This
is necessary for accurately comparing radioactive sources.
The rate-meter function is ideal for contamination survey work and instantaneously displays the counts per minute
(CPM) or counts per second (CPS).
The ST365 comes in two models. The ST365A, with extra-large LED's, provide a digital display that is clear and
visible, even under bright ambient light or the ST365B, with a back lit Liquid Crystal Display (LCD), which provides
the user with a more interactive interface.
The provided desktop computer software, Spectrum Techniques Ultra, enables classroom demonstrations of nuclear
experiments. An instructor or student(s) can run experiments on a wired connection from a PC running Microsoft
Windows or from a Mac computer by a USB or LAN interface. If your computer is capable, the user can also connect
via Wi-Fi.
The Spectrum Techniques Ultra software saves data in spreadsheet compatible files and can graph the detector
results during an experiment.
The Spectrum Techniques Ultra software includes one mode that recycles counting after reaching a preset time and
another mode that automatically increments the high voltage after each cycle. The first mode is useful for performing
radioactive decay studies while the latter is useful for plotting GM detector plateaus.
Teachers and students can also down load the Spectrum Techniques Ultra software for Android devices to allow
instrument control and data display and capture.
IDENTIFYING YOUR MODEL
Model: ST365A
Model: ST365B
