An improved gamma controller assembly to facilitate reliable downhole measurement of naturally occurring radiation is disclosed. The gamma controller assembly includes multiple gamma sensors, a micro-controller, memory, and input/output ports among other components. The multiple gamma sensors detect radiation and output pulses that are received by the microcontroller. The sensor data can be checked, selected, and averaged by the microcontroller, and sent uphole to another microcontroller or computer that can then further process, communicate, and display the data. The sensor data can be averaged and stored to memory or stored as independent values to memory. The gamma controller assembly can be configured to run algorithms that detect if one gamma controller appears to be malfunctioning and, if an apparent malfunction has occurred, adjust the sensor data that is being sent uphole.