The Medusa Radiometrics MS-350 is a lightweight and robust gamma-ray sensor developed with unmanned aerial vehicle (UAV) applications in mind. These systems are fully self-contained as they integrate data acquisition, processing and storage into a single embedded system. 

The MS-350 can also easily be used as a handheld system, operated from a smartphone or tablet PC using the Medusa Detector Operation System (mDOS)


The system comprises a 3x3 inch (350 ml) CsI-based scintillation detector connected to a tailor-made spectrum processing unit. This unit contains a 4096-channel MCA, an RTK-ready GPS, real-time data processing and embedded storage. The system works as a stand-alone unit, and the data can be viewed by connecting to the interface via WiFi or ethernet on a cabled connection. 

The unit runs the  Medusa Detector Operation System (mDOS) that provides access to the multiple functions of the device:

  • Set-up of the system;

  • Status view to inspect data and functioning of the system;

  • Single and continuous measurement modes;

  • View the data in real-time plotted on a map;

  • Download data for custom post-processing.

The data is stored in records containing energy-stabilized gamma-ray spectra, with count rate and activities of 40K, 238U, 232Th and 137Cs. Other radionuclides can be added on request. The data is geo-referenced using the built-in GPS.

System Operation

The system is designed for minimum operator interaction. It provides various views on the data streams while being acquired, allowing for online system checks. The system has embedded data storage with a standard capacity of 16GB, yielding space for over 700 hours of continuous data logging. The system can be user-configured to output gamma-ray spectra continuously, connecting the sensor to multiple data acquisition systems.


Key Parameters

  • High sensitivity

  • Lightweight and rugged carbon housing

  • CsI scintillator for enhanced stability

  • Full spectrum recording

  • Automatic gain stabilization

  • Online nuclide-specific count rates

  • On-board data logging

  • Set up, control and viewing of data via the built-in web server running mDOS

Radiation Sensor

  • CsI crystal, other crystal types on request

  • Dedicated Spectrum Processing Unit comprising

    • 4096 channel MCA,

    • Spectrum stabilization

    • Nuclide-specific data

System Data

  • Housing: Carbon fibre; end caps: Anodized aluminium

  • Connectors: one 8-pin LEMO Artic grip M-series

  • Environmental: 
    -40 0C to +85 0C; 
    IP68 protected

  • Power input 5-35V, (3W nominally, 6W max)

  • Data acquisition rate: up to 1Hz

  • Data storage capacity: 16GB internal

  • Wireless connection via WIFI and Bluetooth

  • Battery-powered

  • Connectivity: user-configurable output streams over IP or serial link