Abstract: A device for playing back a music or video source such as a digital audio tape recorder, Compact Disc, Laser Vision Disc, video tape recorder, television and FM broadcasting and analog records comprises means responsive to control information supplied from a music or video source device for controlling an externally controllable electrical or electronic musical instrument so as to perform the musical instrument automatically in synchronism with playback of the source device. An electrical or electronic musical instrument is performed automatically in synchronism with playback of a source so that a reproduction atmosphere which cannot be obtained by mere playback of the source can be created.

Abstract: An automatic frequency scanning radio receiver which includes a phase-locked loop frequency synthesizer serving as a local oscillator circuit and a scan clock counter circuit to produce a program input signal. The program input signal is supplied to a programmable divide-by-N counter of the frequency synthesizer, whereby the frequency synthesizer has its output frequency automatically changed in steps to automatically scan channels within a desired received frequency band. A detection circuit is provided for detecting a tuning of the radio receiver to a broadcast signal above a predetermined input level on one channel, whereby scan clock counting of the scan clock counter circuit, or the automatic channel scanning is interrupted when the radio receiver is tuned to such a broadcast signal.

Abstract: In a muting arrangement of a radio receiver using a phase-locked loop frequency synthesizer as a local osicillator, a detector detects an in-lock or out-of-lock state of the phase-locked loop through an output state of a phase comparator included in a feedback loop of the phase-locked loop frequency synthesizer, and a mute gate provided in a signal transmission path of the receiver is operated to mute an audio output when the phase-locked loop is out of lock. An indicator may be provided for visually indicating that the phase-locked loop is in lock.

Abstract: Musical tone signals are produced in an electronic musical instrument by calculating the amplitudes at successive sample points of a complex waveshape and by delivering these calculated amplitudes one after another in time sequence. A recursive algorithm is implemented to calculate each amplitude, using one or more sets of parameters and also the calculated amplitudes for a plurality of the preceding sample points. This musical instrument can produce a variety of musical sounds which realistically simulate those of the various existing natural musical instruments including percussion instruments, simply by suitably determining the parameters.