Dual capstan tape transport having controlled tape tension

Claim 1

A tape transport for use with transducer means to transport tape along a predetermined path extending past said transducer means, comprising: two capstans, each disposed at a respective end of said predetermined path; two rollers, each disposed adjacent a respective one of said capstans and arranged to guide tape beyond the respective end of said path in partial wrapping engagement about its respective capstan; two drive means each coupled to a respective one of said capstans; and control means coupled to said drive means and arranged to control operation thereof to drive said capstans at differing torques whereby to induce a controlled tension in tape extending along said path; wherein said control means has a first servo-control loop known per se including one of said drive means and responsively coupled to an independent source of oscillatory signals to control the operation of said one drive means in accordance with the frequency thereof, and wherein said control means has a second servo-control loop including the other of said drive means and normally responsively coupled to a controlled source of oscillatory signals to control the operation of said other drive means in accordance with the frequency thereof, the controlled source being responsively coupled to said first servo-control loop to generate its oscillatory signals in dependence upon the operation of said one drive means.