The true innovation in the smart meters is their ability to relay power consumption statistics without direct contact from a meter reader. Our Elster meter accomplishes this by sending encrypted signals on the 900 MHz ISM band. The antenna can be seen on the rear side of the board near its bottom edge.

Elster meters only relay information when they are spoken to by other meters in the mesh. When they relay information the amount of RF radiation emitted is ~1/4 W, which is less than most cellular phones.