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Detector, Solar Radiation, Magnetic Electron Multipier


Display Status:

This object is on display in the Boeing Aviation Hangar room at Steven F. Udvar-Hazy Center in Chantilly, VA.

Detector, Solar Radiation, Magnetic Electron Multipier

Collection Item Summary:

Bendix M306 Continuous Resistance Strip Electron Multiplier, an ultraviolet detector representative of those used on the OSO-F satellite. Utilizes an open cathode magnetic electron multiplier design that does not need to be enclosed in a glass or other insulating envelope since the vacuum required for its operation is supplied by the lack of atmosphere in Earth orbit. A UV photon striking the surface of the cathode at the entrance grid of the device results in the release of one or more electrons. The first of a series of permanent magnets then directs the emitted electrons onto a strip of specially coated glass. This results in the release of a large number of secondary electrons. Repetition of this process leads to a cascade of charge. The current gain can be as high as 10 million fold. The detector was transferred to NASM by NASA (GSFC) in 1988.

Collection Item Long Description:

Data Source

National Air and Space Museum


Do not reproduce without permission from the Smithsonian Institution, National Air and Space Museum


Credit Line

Transferred from the National Aeronautics and Space Administration


  • Block - metal
  • Cathode - corrugated gold
  • Tubes - metal


  • Other: 3/16 in. diameter x 1 in. tall x 1 in. long x 3/4 in. wide (0.5 x 2.5 x 2.5 x 1.9cm)
  • Other: 2 1/2 in. diameter (6.4cm)

Country of Origin

United States of America



Inventory Number