The method of switch dual GM counter tube

The method used a portable radiation meter, inside the instrument using two high range and low range, high and low range of the measurement process is the key technology automatically converted. Conventional circuit using anodic conversion, high-voltage relays or other high-voltage switching device, The method uses cathode conversion circuit, the circuit by the transistor, low-voltage normally relay, The circuit has low voltage switch, high reliability, low power consumption (authors)