RCL Mark 2, Model 1 Proportional Counter (1950s)

This is a BF3 thermal neutron detector produced by Radiation Counter Laboratories (RCL) of Skokie, Illinois.

The brass chamber is approximately 18 1/2 inches long, 2 inches in diameter, and weighs 3 pounds. The ends are coated with a soft plastic for protection (this was probably done by the user rather than the manufacturer). The operating voltage (1400 to 3200 volts) would have depended on the fill gas pressure - the higher the pressure, the higher the operating voltage.

The RCL detector designation is the Mark 2, Model 1, Serial 1347.  The Model 1 is enriched to 96% boron-10 whereas the Model 2  would have employed natural (20%) boron.

Donated by Ron Kathren


U.S. Atomic Energy Commission. RIB-8. Radiation Instrument Catalog No. 3. July 1, 1952. page BP-A5.

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Last updated: 05/10/11
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