CONTROL SYSTEM FOR TAPE TENSION

PURPOSE:To always secure an optimum envelope by using a signal including the signal to indicate the envelope condition of the waveform of the regenerative signal as the signal to control a tape tension. CONSTITUTION:For the regenerative signal from a tape 1-1, the envelope of the waveform of the regenerative signal is detected, for example, by a rectification circuit 5 and a low pass filter 6, thereafter, the amplitude size of the envelope is obtained as a digital signal value by an A/D converter 7. It is required for the regenerative envelope that the amplitude is large and flat. The mean value or deviation value of the envelope can be calculated out of the digital signal by a microcomputer 9 or a special IC (an integrated circuit). That is, by changing the tape tention so as to satisfy the above-mentioned conditions, the envelope can be reproduced in the optimum conditions, and the reproduction with few code errors is attained.