ECL Model EC 6 "Bismo-Count" GM Detector (ca. 1955-1960)
The Model EC 6 "Bismo-Count" survey meter was built by Electronic Counter Laboratories Inc. at 418 South Pecan St., Los Angeles, California. It was primarily intended for uranium prospecting.
The fact that it is called the Bismo-Count indicates that it used a Victoreen bismuth 6306 GM tube. Alas, the tube is missing in this example. Even though the 6306 was more sensitive than Victoreen's 1B85 (used in ECL's Electro-Count), the range of the Electro-Count and the Bismo-Count are the same. They also employ the same count rate to exposure rate calibration (400 cpm = 0.1 mR/hr).
Detector: GM tube
Range: 0-0.2, 0-2.0 and 0-20.0 mR/hr
Size: 4.5" x 9.5" x 5"
Batteries: One 22.5 volt (e.g., Eveready 412) two 45 volt (e.g., Eveready 455) and four 1.5 volt D cells
Kindly donated by Chuck Abraham.
Electronic Counter Laboratories Inc. Operation Manual. No date.