High range instrument - .02 – 500 R/hr. ~ Radiation Detector – ioniziaton chamber ~ Batteries – 2 “D” cells ~ I subminiature triode vacuum tube, 1 transistor ~ Controls – range switch – circuit test, off, 0 - .5, 0 – 5, 0 – 50, 0 – 500 R/hr. – meter zero control ~ Yellow metal case. Replaced earlier high range detectors.
This was the best and most widely used high range radiation meter. The grid leak resistor (glass incased) on the tube is a whopping 220,000,000 ohms and the tube and switch circuit have to be spotless and totally dry for this instrument to function. No where else have I seen a resistor this high - ever!
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