This report describes the design, development, fabrication, and testing of ruggedized prototypes of a Portable Beta-Gamma Survey Instrument. This instrument measures beta and gamma radiation over the range of 1 mr/hr to 10,000 R/hr in seven linear decades. An ionization chamber is employed as the beta-gamma detector, and the signal output from this detector is coupled to a d.c. electrometer. The ionization chamber is designed to provide a sizable beta window to permit evaluation of wide area beta contamination. The input stage of the electrometer is a CK 5889 vacuum tube, with all subsequent stages of amplification using solid state components. The unique design of the electrometer and associated power converter provides approximately 90 hours of operating life from two type BA-30 batteries. (Author).

Three Radiac meters, Model IM-189/U(XV-1) were tested. Several discrepancies in operation due to the environments were noted.

The gamma beta ray survey meter is a portable electrometer instrument suitable for measuring gamma and beta radiations. It has been described in CP 1930.

A low range beta-gamma survey meter employing halogen-quenched G-M tubes and transistor circuitry has been developed. The instrument measures gamma radiation from 0 - 500 mr/hr in four linear ranges and provides beta indication on all ranges. The instrument has been conservatively designed to meet military specifications. A transistor oscillator converts battery voltage to regulated high and low voltages, giving more than 400 hours of operation with two easily obtainable flashlight cells. The use of a corona regulator has been avoided. The rate meter is an advanced zero-stable diode pump circuit requiring no pulse-width range switching. The survey meter has been packaged in a form providing easy handling with one-hand operation for some monitoring applications. The instrument is also alpha sensitive, reading an equivalent 2 mr/hr in contact with a plutonium source of 5.10-3 microcuries/cm2.