An end predictor is provided for use with a tape cassette of the type which contains a measured length of tape corresponding to a given number of turns on one of the tape hubs mounted therein when the tape is entirely wound on one of the hubs, exclusive of its leader portion extending to the other hub....http://www.google.es/patents/US4044233?utm_source=gb-gplus-sharePatente US4044233 - End predictor for cassette tape
