A process for the optical detection of objects moved at a conveying speed. The spiral inductor is arranged on top of the transistor, whereby an electromagnetic coupling between the spiral inductor and the transistor is not typically possible to avoid. A spring-biased pawl on the hub engages a tooth of an inner gear on the drive gear to provide a driving connection between the hub and the take-up gear when the motor drives the hub in a first direction but effectively releases the driving connection when the take-up gear is manually rotated while the motor is idle. In order to implement the decode and carry function as a centralized function, there arises a requirement that logically adjacent decode circuits should be physically close together to minimize the overhead of the carry wiring. The docking station has greater cooling capacity than the portable computer alone to provide enhanced cooling of the high power mode of operation. The compound is useful as a photographic cyan coupler.