20th Century Electronics Proportional Counter (ca. 70s)


This neutron detector was produced by 20th Century Electronics  in England.  The company began manufacturing BF3 counters in the early 1950s. It is 9 1/2 inches long, 1/2 inches in diameter, copper walled and filled with BF3. One end (towards the right in the above photo) has a threaded cap to protect the fragile glass insulator. 

The model number, marked on the wall of the tube, is 5EB40/13/UA2528.  The EB refers to "enriched boron trifluoride."  The 13 refers to the tube diameter, i.e., 13 mm.

Donated by David Allard

Proportional Counters                   Museum Directory

Last updated: 05/10/11
Copyright 1999, Oak Ridge Associated Universities