The Manual Drive Tape Player is a device that allows a user to manually play an audio tape at speeds other than the nominal rate. The Manual Drive Tape Player is comprised of 2 parts: the deck and the crank, both of which are derived from 1 old Sony Walkman and about $5 worth of parts. The audio from the headphone jack can be run into any amplifier, mixer, or computer.
The deck is made by removing the motor and gears that spin the spindles, as well as removing the spindles themselves [the motor and gears can be thrown away, but NOT the spindles: those are used later]. It is important to leave the mechanism that moves the tape head into and out of place in tact [in other words, leave the Play mechanism alone].
The crank is made from a simple casement window crank [about $3 at a hardware store]. One of the spindles removed from the deck is turned upside down and mounted on the bottom of the crank. Modelling putty from a game or hobby store works well and is fairly cheap. Once complete, put in a tape, insert the crank into the tape as shown in the first picture above, press Play to move the tape head into place, and spin the crank.
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