The application of solid state technology to medium power UHF television transmitters

The introduction of any new or extended technology into a product has to give the end user some tangible benefit. In today´s increasingly commercial environment these benefits are generally required to have an impact on cost. There are different types of cost each impacting at a different time in the life cycle of the product. One of the main elements of cost which has driven the progressive implementation of solid state technology in transmitters, is the perceived improvement in reliability partly brought about by the elimination of finite lifetime devices like tetrodes. Following a brief historical overview, the author looks at present transmitter designs, covering: amplifiers; precorrection; power supplies; combining; output stabilisation; and monitoring. Finally, the total cost of ownership of a transmitter system is considered under the headings of capital costs and operating costs