Abstract: A method and apparatus for producing special motion effects such as slow or fast motion, still frame and other effects from video magnetic tape is disclosed which is particularly applicable to helical wrap recording and reproducing apparatus. The apparatus employs a transducing head that is mounted on a revolving scanning drum, with the head being movable in a line generally transverse to the recorded track. The present invention utilizes the transverse positioning of the head to accurately follow a track during reproducing or playback and, at the completion of the track, to properly position or set the head in position to either play the next adjacent successive track, replay the same track, or play yet another track so that special motion effects can be achieved without experiencing picture breakup or unwanted noise.

Abstract: A bar code reader system includes a stream of pulses whose period is a function of the scan speed of the reader as it scans the bars and spaces of a bar code symbol. Transition pulses are supplied which identify the boundaries of the bars and spaces. The tach pulses which occur between transition pulses are counted, loaded into memory, and are read from memory via microprocessor means, whereby the widths of the bars and spaces are determined. The sequence of the bar and space data is decoded to yield the bar code encoded numbers.

Abstract: A method of operating a signal recording and reproducing apparatus is disclosed whereby generally continuously and noise-free transfers of signal information are obtained while reproducing the information from a magnetic tape being transported at a changing speed. The apparatus is of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing. While the tape is transported at speeds other than the normal record and reproduce speed, transport derived signals are employed to control the tape transport servo. When the normal speed is attained, the reproduced signal is detected to determine whether synchronous reproduction conditions have been achieved. If synchronous reproduction conditions are not achieved, the transducing head is moved to a new track to effect synchronous reproduction of the signal information.

Abstract: Apparatus is disclosed for providing full frame reproduction, i.e., the reproducing of two consecutive video fields, during a still frame or stop action mode in a recording and reproducing apparatus of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing, and at the completion of the reproduction from the track, to properly position the head to either reproduce the next desired track or to again reproduce the same track. The present invention has the capability of reproducing two consecutive fields to obtain full frame picture resolution in the video display in the manner whereby the transducing head which is carried by a movable element is maintained relatively centered within its dynamic range so as to minimize the possibility of picture break-up due to mistracking.

Abstract: In an apparatus for automatically maintaining a transducing head assembly on the proper track, which is particularly adapted for a helical scan recording and/or reproducing apparatus capable of providing special motion effects, movable head automatic position acquisition circuit and method is disclosed. The apparatus is of the type which utilizes transverse positioning of the transducing head assembly to accurately follow a track during reproducing, and at the completion of the reproduction from the track, to properly position the head in position to either reproduce the next adjacent successive track, reproduce the same track or reproduce another track so that the appropriate special motion effect is achieved. In the still frame motion mode of operation, the head is normally reset to rescan one or more tracks repetitively by a head tracking servo.

Abstract: In an apparatus for automatically maintaining a transducing head assembly on the proper track, which is particularly adapted for a helical scan recording and/or reproducing apparatus capable of providing special motion effects, an automatically compensated movable head servo is disclosed. The apparatus is of the type which utilizes transverse positioning of the transducing head assembly to accurately follow a track during reproducing and, at the completion of the reproduction from the track, to properly position the head in position to either reproduce the next adjacent successive track, reproduce the same track or reproduce another track so that the appropriate special motion effect is achieved. Proper tracking is maintained by applying a small oscillatory motion to the head to cause it to vibrate laterally of the track, examining the resulting modulation of the reproduced signal's envelope to generate a tracking error correction signal and applying the error correction signal to the head assembly.

Abstract: A method of operating a signal recording and reproducing apparatus is disclosed whereby generally continuously and noise-free transfers of signal information are obtained while reproducing the information from a magnetic tape being transported at a changing speed. The apparatus is of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing. While the tape is transported at speeds other than the normal record and reproduce speed, transport derived signals are employed to control the tape transport servo. When the normal speed is attained, the reproduced signal is detected to determine whether synchronous reproduction conditions have been achieved. If synchronous reproduction conditions are not achieved, the transducing head is moved to a new track to effect synchronous reproduction of the signal information.

Abstract: In an apparatus for automatically maintaining a transducing head assembly on the proper track, which is particularly adapted for a helical scan recording and/or reproducing apparatus capable of providing special motion effects, track selection method and apparatus is disclosed. The apparatus is of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing and, at the completion of the reproduction from the track, to properly position the head in position to either reproduce the next adjacent successive track, reproduce the same track or reproduce another track so that the appropriate special motion effect is achieved. During the acceleration of the tape to normal speed, the tape transport is initially controlled relative to a recorded control track to position the head relative to the recorded tracks so that the reproduced video signal is color framed with respect to studio reference.

Abstract: A method and apparatus is disclosed for automatically maintaining a transducing head on the proper track and is particularly adapted for a helical scan recording and reproducing apparatus that is capable of providing special motion effects, such as slow, still and fast motion, and other effects. The apparatus is of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing and, at the completion of the reproduction from the track, to properly position the head in position to either reproduce the next adjacent successive track, reproduce the same track or reproduce another track so that the appropriate special motion effect is achieved. To provide accurate head tracking, a small oscillator motion (dither) is applied to the head to cause it to vibrate laterally between two limits relative to the track. This causes amplitude modulation of the reproduced signal, which is in the form of an RF envelope of frequency modulated carrier.

Abstract: A method and apparatus is disclosed for automatically maintaining a transducing head on the proper track and is particularly adapted for a helical scan recording and reproducing apparatus that is capable of providing special motion effects, such as slow, still and fast motion, and other effects. The apparatus is of the type which utilizes transverse positioning of the transducing head to accurately follow a track during reproducing and, at the completion of the reproduction from the track, to properly position the head in position to either reproduce the next adjacent successive track, reproduce the same track or reproduce another track so that the appropriate special motion effect is achieved. The apparatus of the present invention produces a continuous stable, noise free video picture without breakup, when the apparatus is switched from one mode to another, i.e., from a slow/still motion mode to a normal speed reproducing mode.

Abstract: A magnetic head, rotating at high speed in a reproduce relationship with a magnetic tape, is supported on the free end of a piezoelectric bender element. The bender element is caused to vibrate between two limits at a fixed frequency (dither) to determine the instantaneous position of the magnetic head relative to a track of data recorded along the tape. A feedback servo provides continuous adjustment of the position about which the transducer is vibrated so as to maintain the magnetic head in an optimum reproduce relationship with respect to the track.

Abstract: Improved deflection of a bimorph having a pair of electrically poled piezo-ceramic elements bonded to opposite sides of a common substrate is achieved by applying to each element a deflection voltage whose polarity is always in the poling direction of the element to which it is applied. By maintaining the polarity of the deflection voltages in the poling direction of the piezo-ceramic elements, large amplitude deflection voltages can be used without de-polarizing the piezo-ceramic elements.