> The theory of operation is that there is a static charge in the atmosphere. > The radio active particles keep the sensors from building up any static > charge. They used 4 sensors in 2 pairs. one on each wing tip for roll > stabilization, and one on the nose and tail for up and down stabilization. > The sensor were then input to a op amp and the output from it tied into the > radio control servo of the necesary control. > >> >What are the sensors detecting as a reference field? The ionosphere? > >Mark A. Corio >Rochester MicroSystems, Inc. No, it's sensing the electric potential that naturally exists in the atmosphere, the same one responsible for lightning. With a sensitive instrumentation amp you can measure the voltage difference between your feet and your head (usually a couple hundred volts over six feet). --BN ---------------------------------------------------------------------------- Country Robot "Modular robot components 69 S. Fremont Ave. # 2 for education and industry" Pittsburgh, PA 15202 ----------------------------------------------------------------------------