Prague high-power broadcasting equipment

This paper is a very complete description of the new broadcasting station erected near Prague with a C.C.I.R. rating of 200 kW. The studios are situated some 35 km. from the transmitter, which is of the most modern design and has a frequency characteristic such that the variation in transmission efficiency over the range 30 to 10,000 ~ does not exceed 3 db. Balanced push-pull circuits are used throughout the equipment with stated precautions to prevent spurious oscillation and give minimum distortion with great case of tuning. To enable the transmitter to be tested and adjusted without causing interference an artificial aerial is provided and consists of a non-radiating water-cooled resistance capable of dissipating 200 kW. The paper is well illustrated and also gives details of the power supply, the cooling plant and the buildings.