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Among the test signals used for measuring the transmission performance of television links are `sine-squaredÂ¿ and `smoothed-barÂ¿ pulses. The paper gives details of the design of a test-signal generator which, at the line-frequency repetition rate, produces a composite waveform consisting of a sine-squared pulse, a smoothed-bar pulse and a normal line-synchronizing pulse. The sine-squared pulse may have a half-amplitude duration of either T or 2T, as selected by a switch, where 1/2T is the nominal upper frequency of interest in the television system (e.g. 3Mc/s in the British 405-line system). The bar pulse has a duration of approximately one-half of the line period and has transitions of `integrated sine-squaredÂ¿ shape. To facilitate precise measurements the generator has been designed with particular emphasis on stability of waveform shape and freedom from jitter. Consideration is also given to analogous test signals for colour-television systems.