The AIR-EAGLE XLT TX Is an R.F. transmitter capable of sending four independent dry-contact input commands to an Air-Eagle XLT Receiver located up to 2500 feet away (longer ranges can be achieved with external high gain antennas). Any number of transmitters and receivers can be combined to create a long-range radio frequency system that operates hazardous or hard-to-reach electrical apparatus from safe, convenient locations. Eight user-selectable frequencies allow multiple systems to operate simultaneously in the same area without interference.