The General Dynamics SATCOM Technologies (GDST) Model 7134 Antenna Control System is a microprocessor-based system incorporating digital technology for accurate antenna positioning with high reliability, maximum flexibility, and a straightforward and practical user interface. This control system is ideally suited for small to medium aperture antenna applications requiring capabilities for automatic multiple satellite access, program track, remote control via an RS-232 or RS-422 communications link, and optionally automatic step track operation and memory track. The standard product provides 2-speed axis control for AZ and EL with a high/low speed ratio of up to 15:1. This is accomplished by application of user-settable high and low-speed control signals to variable speed AC drives, which in turn control standard 3-phase induction motors. For 3-axis systems, circuitry is provided for the control of an AC synchronous stepping polarization motor. The AZ and EL motor controllers employ integral electronic protection. The drive cabinet includes NEMA-rated circuit protection devices for each motor/motor controller, which are sized appropriately for each application.