Abstract: The battery holder enables rapid insertion and removal of a battery relative thereto. An open portion of the holder provides ready access for rapid and efficient battery insertion and removal. Biased contacts and a protruding lip portion at opposite ends of the battery holder securely retain the battery therein.

Abstract: A device for enabling detecting of the time code word prerecorded on each frame of videotape, for use in videotape production functions. The device is adapted to enable locking onto time code input signal frequencies rapidly and efficiently over a wide range of videotape running speeds. It is further adapted to enable detecting of errors in the time code input signal efficiently and effectively. The device includes an input signal frequency locking circuit, including at least one phase lock loop, responsive rapidly over a wide range of videotape running speeds for enabling decoding of difficult-to-read time code, and for generating the circuit clock frequency. The device further includes a valid sync word detecting circuit, including a counter, and a pulse counting circuit, including at least one counter, for detecting error in the time code signal and preventing loading of invalid time code.

Abstract: A method and apparatus are disclosed for converting a parallel binary coded, input number from a first unit system to a second unit system, the two unit systems being related by a known numerical conversion factor. The parallel binary coded input number is converted to a number of serial pulses equal to the coded number and the serial pulses are fed to a counter provided with feedback. The feedback operates on the counter to reduce the count of serial pulses by a selected numerical conversion factor to thereby effect the desired conversion.The counter output typically includes a converted number expressed in the second unit system and a remainder number expressed in the first unit system, the remainder being smaller than the numerical conversion factor.

Abstract: There is disclosed apparatus suitable for use in conjunction with film editing tables or other devices requiring precise control over shaft rotation speed, that is, apparatus for interlocking two or more shaft rotating systems to rotate one or more slave shafts in precise speed synchronism with one remote master shaft. For each slave shaft to be controlled, there is provided a differential amplifier connected in a velocity servo loop designed to force the slave shaft to rotate in precise speed synchronism with a remote or line master shaft. The primary feedback loop comprises means for generating trains of pulses having a characteristic representative of each of the rotational speeds and for deriving from these pulse trains analog voltages which are applied to a differential amplifier to produce an error signal to be driven to zero for controlling the speed of the slave shaft.