Abstract: A hybrid system (18) for control and monitoring of an amplifier (330) is provided. The hybrid control system (18) includes an analog control subsystem (81) and a digital control subsystem (82). The analog control system provides an automatic gain control loop for maintaining the gain of amplifier (330) at a predetermined level. The digital control subsystem (82) monitors a plurality of operating characteristics of amplifier (330) and commands the analog control subsystem (81) to reduce the gain of amplifier (330) responsive to certain predetermined fault conditions. The digital control subsystem (82) shuts down amplifier (330) responsive to other predetermined fault conditions. The digital control subsystem (82) also controls the power-on sequence and power-down sequence for amplifier (330), insuring that the gate bias voltage is first applied or maintained before the drain voltage is applied or removed.

Abstract: A UHF transmitter for digital TV signals includes, for example, twelve silicon carbide transistor RF output power amplifier panels driven in parallel by two silicon carbide amplifier driver panels and where each panel is comprised of two modules each further including a 180.degree. signal splitter, a pair of quadraphase signal splitters and combiners, a 180.degree. signal combiner, and five RF amplifier pallets which themselves are comprised of two silicon carbide transistors located on a common flange and operated in push-pull relationship so as to suppress even order distortion products and reduce sensitivity to ground currents. A monitoring system, including a touch screen control display and control panel senses the status of all assemblies so as to allow an operator to control the transmitter and inquire about the status of the various components and power supplies, and to replace one or more units as required without the need for turning the transmitter off.