Tracerlab TGC-5 GM Tube (1953)

Tracer TGC 5 GM Tube

The TGC-5, produced by Tracerlab Inc. of Boston Massachusetts, is a glass-walled GM tube designed for use with survey instruments. Tracerlab noted that the TGC-5 was also suitable for dip counting wherein the end of the tube was submersed in a solution as a means to estimate the beta activity.  

Tracer TGC 5 GM Tube

The earliest reference I have for the TGC-5 is the July 1949 issue of Nucleonics.

Size: 6” long and 0.75” inner diameter

Wall: Glass, 30 mg/cm²

Anode: Tungsten central wire

Cathode: Stainless steel coating on inside of glass wall

Operating voltage: 900 V

Plateau length: 150 volts

Fill gas: Argon with organic quenching agent

Fill gas pressure: 260 mm Hg

Dead time: ca. 90 us

Base: Four prong ceramic base

Price: $18 in 1952

The shipping container used by Tracerlab is shown to the right. When shipped by air, the pressure drop could damage the tubes. As such, the container was hermetically sealed.

The paperwork that came with the tube is dated 7-2-1953.


  • Nucleonics, July 1949, inside cover.
  • Nucleonics, November 1949, inside cover.
  • Tracerlog, No. 43, April 1952.
  • Tracerlog No. 45, September 1952.