El-Tronics Model DS 7A "Classroom Demonstrator" (1952 - 1955)
"A classroom demonstrator for use with Geiger tubes to demonstrate the
properties of radioactivity by both visual and audible methods" according
to the Atomic Energy Commission Radiation Instrument Catalog.
A radioactive sample was included with the instrument but it is missing in this example.
The earlier version of this instrument, the Model DS-7, only indicated the count rate via a neon light and a speaker. There was no display indicating the count rate in cpm.
Detector Side-wall GM tube in external probe.
Display: Indicates count rate in cpm and the applied high voltage in kilovolts.
Range: 0 – 200, 0 – 2000 cpm.
High Voltage Supply: up to 1000 volts
Output: speaker and neon light
Size: 9.5” x 7” x 9.5”
Weight: 16 pounds
Kindly donated in memory of Syd Porter
AEC Radiation Instrument Catalog No. 3. Page MGM-24B. July 1, 1952.
Copyright 1999, Oak Ridge Associated Universities