Manmade radio signals (from wireless devices, orbiting satellites, spark plugs, microwave ovens, etc.) swamp the weak waves we detect from objects out in space. Before we install any piece of equipment in Green Bank, we test it in this special room called an anechoic chamber. The pedestal in the foreground holds the device to be tested, and an antenna at the back of the room picks up its radio waves, if any. The foam cones covering walls, floors, and ceilings break up radio waves that are not in direct line with the antenna. Any radio-leaking electronics are encased before they are brought close to the telescopes.