El-Tronics PR-5A GM Survey Meter (1955-1960)

This GM survey meter was manufactured by El-Tronics Inc. of Philadelphia sometime in the mid to late 1950s. 

Unlike the Model PR-5, which had an external probe, the GM tube of the PR-5A is located inside the case  - the detector window can be seen in the lower right hand corner of the case in the above photo. The glass-walled GM tube was manufactured by RCL.  

Quoting a 1955 advertisement: "Three Range Portable Geiger Counter. Highly sensitive, with internally mounted G.M. tube designed for prospecting under rugged conditions! Waterproof meter. Flashlight batteries. Comes with strap. Alnico magnet earphone. Model PR-5A - $99.95."

 

Range:  0 - 0.2, 0 - 2.0, 0 - 20 mR/hr

Size:  ca. 4"  x  8"  x  4"

Output:  No speaker but it has a phone jack and a neon light the flashes of which indicate the count rate.

References  

Atomic Energy Commission.  Radiation Measuring Instruments, RIB-8 (supplement 2). July 1, 1954. Page SGM-111A.

Advertisement. Saturday Evening Post. July 16,1955. Page 87.

Museum Directory              Survey Instruments

Last updated: 12/06/11
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