IM-113A/PDR
Beta / Gamma Survey Meter
IM-113A/PDR
Beta / Gamma Survey Meter
A unit of RADIAC set AN/PDR-46
Measures 0 - 20 Milliroentgens / Hour
3 Scales: 0 - 0.2 / 0 - 2.0 / 0 - 20 mR / Hour
Serial Number: 18 Built in 1957
Manufactured By: Nuclear-Electronics Corporation
Nuclear-Electronics Model: XX2 Serial Number: 1269
Unit uses (3) 300 volt dry battery, type BA-291, (2) 45 volt dry battery, type BA-56,
and (1) 1½ volt dry cell, type BA-65
This model uses a Geiger Mueller tube to detect beta and measure gamma radiation.
Detection is indicated on the meter over 3 scales, through the optional headphone, which
uses a standard ¼" jack, and by a neon indicator bulb just below and left of meter face.
The probe has a sliding beta shield. The case is made of aluminum and waterproofed.
Unit Measures: 6" wide x 9¼" long x 6½" tall.
Close-up of nameplate and meter face.
Inside View
Geiger Mueller Probe
The glass GM tube is 5" Long. The probe housing is made from aluminum and has a rotating beta
shield. The red rubber ring goes over the GM tube to keep it from moving around in the probe housing.
The overall length of the probe housing is 7".