The Reproduction of Signals recorded on Magnetic Tape

The conventional analysis of the action of the ring reproducing head is re-examined and experiments are described which demonstrate divergences between the theoretical and practical results. The action of a reproducing head consisting of a single loop of non-magnetic conductor is analysed and experimental results which verify the theory are given. The effects of various common imperfections and maladjustments in all the types of reproducing head are predicted and checked by experiment. The findings are then applied to the problem of frequency-characteristic calibration, and the corrections which are necessary to obtain consistent results with various heads are ascertained. The practical aspects of standardization are discussed, and the possible application of special heads in this and other roles is noted.