tape timer - measures tape runs in real time

tape timer elektor march 1984 The accurate measurement of a tape run requires monitoring the length of tape that passes a point in a given period. The only realistic method is counting the revolutions of a free-running idler wheel in the tape path. Several designs have been published for digital tape counters which display true elapsed time, but to the best of our knowledge all have the serious disadvantage of requiring a very-high- tolerance pulley. In the present design this is not required, because any size pulley can be electronically "tailored" to work accurately: the deviation can be kept to within half a second per hour. . . . measures tape runs in real time The modest role of the tape counter sometimes creates the impression that it is a superfluous device. This is, of course, not so because it is virtually impossible to find a particular passage on the tape without the counter. Determining the dur- ation of a recording, or how much tape is left on the spool, cannot, howev...