RCL Mark 1 Model 5 Probe Counter (late 1940s)
|This tube, manufactured by Radiation Counter Laboratories of Chicago Illinois, is identified on the label as the Model 1 Mark 5. Unfortunately, I have no literature that refers to this particular model. Its outward appearance is identical to the Mark 1 Model 100 and so the best I can do is provide the following information for the Model 100. The Mark 1 Model 100 was described in the October 1948 issue of Nucleonics as follows: "This thin-walled probe counter has been developed for inserting into small recesses or into regions of high flux density. The diameter is 7 mm and the thin wall section is 15 mm. The gas volume extends up to the handle of the counter and a tubulation permits easy refilling."|
| The AEC Radiation Instrument
Catalog of 1950 described the Model 100 as a "miniature thin wall Geiger
counter tube suitable for internal medical studies."
Size: 17 cm long, 7 mm diameter
Quench Gas: organic (Model 100)
Wall: glass, thickness 30 mg/cm2 (Model 100)
Cathode: Clear metallic coating (tin?)
Operating voltage: 850 volts (Model 100)
References for Model 100:
Atomic Energy Commission Radiation Instrument Catalog No. 2 Part 1. 1950, page BG-2A8A, page date June 1, 1949.
Nucleonics October 1948 page 83.
Nucleonics May 1952, page 89.
Donated by the Atomic Energy of Canada Limited at Chalk River.
Last updated: 07/25/07
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