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The paper describes the design, construction and service performance of the Sutton Coldfield television station built by the British Broad-casting Corporation as a first step in the extension of its television service to the provinces.The relation of the operating channel of Sutton Coldfield to the overall frequency-allocation plan for the 41–68-Mc/s band used for television broadcasting in the United Kingdom and the reasons for adopting a vestigial-sideband characteristic for the vision transmission are briefly discussed.The complete vision and sound transmitting equipment is described and its performance characteristics are stated. The considerations governing the design of the aerial-mast system, the vision-and-sound-combining diplexer and the transmission lines are also discussed, and details are given of the construction used and the performance obtained.

The paper outlines the requirements of a high-quality sound equipment as supplied to the British Broadcasting Corporation for use in the London Television Station. Design features necessary to meet these requirements are indicated and a general description is given of the complete equipment. The final section of the paper gives information on the overall performance of the apparatus and includes data on the frequency and harmonic distortion of the amplifier equipment.

This Part of the paper sets out the agreed specification of the vision transmitter of the London Television Station. Details of the valves available for meeting the requirements are given, and their calculated performance in the balanced bridge circuit of the final modulated amplifier is outlined. This is followed by an examination of:? (1) The mechanical assembly, with particular reference to the essential features governing the design of the various components. (2) The control of the amplifier by the television signal, and the conditions relating grid input-volts and outputpower to the aerial feeder. (3) Special requirements of the system. The Appendix includes a note on the determination of the compensating capacitance for grid-lead reactance, and general data regarding the transmitter.

Television equipment, in particular that supplied to the B.B.C. for the London Television Station, is described, and the technical considerations which led to its development are outlined. A description is given of the purpose and practical design of the apparatus handling modulation frequencies, which comprises studio equipment, camera control equipment, modulation amplifiers for the radio transmitter, and associated apparatus.Owing to the large amount of equipment covered by these headings, little more than cursory descriptions can be included, making it imperative to omit many details of design. References are therefore made to the relevant patent specifications, from which more detailed information may be gathered.

The transmitter described was designed and constructed for the B.B.C. and is the first post-war vision transmitter to be operated on regular broadcasting service in England. The description is general where the technique is well-established, but becomes more detailed concerning novel parts of the equipment.