The Origin of the Survey MeterвЂ¦ Robley Evans is generally credited with developing the first whole body counter, the purpose of which was to measure the radium burden in the bodies of radium workers. вЂ¦It is a story of the very first radiation survey using a count-rate meter. The year was 1936вЂ¦ a radium-containing industrial radiography source had disappeared at GE facility in Massachusetts. GEвЂ™s insurance company (Liberty Mutual) contacted Dr. Evans at MIT and asked him to help locate the missing source. Evans packed up his count-rate meter, a long extension cable and a GM detector and surveying the plant with his bulky equipment and he located a strong source of radiation coming from an unexpected location: a workerвЂ™s locker!... The radium source was in the pocket of a shirt. The worker was immediately tracked down and found to have a severe skin burn on his chest and on his back, opposite the burn on the front of his body, was a patch of erythema. As Evans recounted the incident,вЂ¦вЂќthose were the days of the wild westвЂќ .. This was the first radiation survey with a Count Rate Meter! from our collection El-Tronics PR-5A an early Geiger Counter El-Tronics Inc. was located in Philadelphia, PA and it was one of the first company which advertised as вЂњDesigners and Manufacturers of Nucleonic and Electronic EquipmentвЂќ, they claimed to be manufacturers of GM counter apparatus for nearly 14 years already in 1948. The El-Tronics PR-5A was designed and manufactured at the beginning of 1950s . It has a built in Geiger Mueller tube (halogen quenched) and it was powered by two flashlight batteries. The three ranges were: 0.2; 2.0 and 20 mR/h.