Instantaneous tape position determination in cassette - involves measurement of transfer speed and physical characteristics of tape

摘要

The instantaneous position of a tape used for recording and reproduction is calculated from constants representing physical characteristics. The speed of transfer of tape from one spool to another is also measured. Pulses are generated proportional to speed or rotation of eachspool in a tape transfer system. High frequency clock pulses are accumulated in registers to determine time of rotation for each spool from the number of pulses generated proportional to speed. Physical characteristic constants for cassette is use are stored in memory and used in calculations to determine tape position.