A SENSITIVE GAMMA SCINTILLATION TRANSISTORIZED MONITOR

摘要

A sensitive gamma monitor was designed with a first-range full scale sensitivity of 0. 015 mr/hr or 10, 000 C/M. Range two and range three are 100, 000 and 1, 000, 000 C/M respectively. The complete instrument (including probe) weighs 17 pounds excluding the chart recorder. The instrument employs a 5-inch diameter phototube and a 5x5-inch NE-102 terphenyl-in-polyvinyltoluene crystal. All circuits are transistorized and are of the plug-in, unitized construction type. The instrument will drive a standard one milliampere chart recorder. The batteries employed will continuously operate the instrument for 150 hours. The complete instrument was temperature-tested from minus 20 F to plus 140 F with no malfunctioning and with a reading error of about. 6, 0 per cent.