Model 115 "Super Scintillator" (1953)

Model 115 "Super Scintillator" (1953)

Manufactured by Precision Radiation Instruments of Los Angeles California, the “Super Scintillator” was one of the first survey instruments to employ a NaI scintillator.The NaI crystal, small by today’s standards, was 1.5” x 1.” The electronics and probe were housed in a 5” x 11” x 14.5” case. Since the Super Scintillator was specifically designed for airborne and vehicle gamma surveys, it allowed the user to set a shorter time constant than was employed with typical hand-held systems—this facilitated operation at high speeds. For surveys from aircraft, the manufacturer recommended speeds under 100 mph and altitudes of 50 to 100 feet. A pilot light was employed to guard against leaving the unit turned on. Two jacks were provided so that it could be connected to a continuous strip recorder.

This particular instrument is of very early construction: the scale on the meter was numbered by hand and the small meter found in later versions on the outside of the case is missing in this example. A stamp in the instruction manual that came with the meter states that it was received by Radiation Instruments Branch, August 12, 1953.

Model 115 "Super Scintillator" (1953)

Range: 0-0.025, 0-0.05, 0-0.25, 0-0.5, 0-2.5 and 0-5 mR/h

Batteries: Eight 1.5 volt, four 67.5 volt, and two 22.5 volt

Dimensions: 3.5" x 12" x 15"

Weight: 16 pounds

Price: $595 in 1954

For some reason, maybe it was just a part of being in LA, Precision Radiation Instruments was also in the music business. While none of the PRI-owned labels (Craftsman, Tops, etc) were household names, they did produce records for some reasonably well known entertainers such as Mel Torme and Lena Horne. One PRI 33 1/3 record worth mentioning: "If the Bomb Falls," a primer on surviving a nuclear attack.

Donated by the U.S. Department of Energy, Oak Ridge Operations.


  • AEC Radiation Measuring Instruments, RIB-8 (supplement 2) July 1, 1954.
  • Precision Instruments catalog, form 1001B, 1954 copyright.
  • Instruction Manual for Model 115 “Super Scintillator,” no date on manual but circuit diagram is dated November 18, 1952 and there is a stamp indicating that the manual was received August 12, 1953.