RCL Mark 1 Model 105 GM Tube  (ca. early 1950s)

The Radiation Counter Laboratories Mark 1 Model 105 is described as a "miniature end window search counter."  Its thin window permits the detection of alpha, beta and gamma radiation, and its small area permits the precise localization of small areas of contamination. The price? $65 in 1952.

Size:  3 1/4" long,  3/4" diameter

Wall: glass

Window:   7 mm diameter and 1 - 2 mg/cm2 thick

Cathode: Inner surface of glass wall coated with aquadag 

Operating voltage:  850 volts

Gas: organic quenched


AEC Radiation Instrument Catalog, page date July 1, 1950

AEC Radiation Measurement Instruments, RIB-8 (supplement 2) July 1, 1954.

Nucleonics May 1952, page 89.

GM Detectors             Museum Directory

Last updated: 07/25/07
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