Four-channel measuring system with NaJ(T1) scintillation counter for gamma logging of shallow boreholes

An equipment for spectrometric measuring of the gamma radiation in wells of 250 m depth is presented. The equipment consists of the following units: downhole probe including a scintillation counter NaJ(T1), a 4-channel pulse-height analyser with an analog to digital converter, spectrum stabilizer, supply source. The pulses from detector to the surface panel are transmitted by a coaxial logging cable. The block-scheme and technical parameters of the spectrometer are given too. (author)