Abstract: A system for compensating and correcting errors in the time base of video signals read from a video disc in which the errors are corrected first coarsely in response to phase differences between horizontal sync signals of the video signals following which a fine correction is made in response to measured phase differences of burst signals of the video signal. A first phase detector produces an output signal in response to phase differences between the burst signals and an output of a reference frequency generator operating at the burst frequency. A second phase detector produces an output signal in response to phase differences between the horizontal signals and the reference signal divided down by a predetermined factor. The output signals of the two phase detectors are summed and then applied to the control input of a variable delay line which adjusts the delay time and hence phase errors in the video signal accordingly.

Abstract: A transposition apparatus for an electronic musical instrument such as an electronic organ is disclosed. The transposition apparatus permits the playing of a musical score in any desired key regardless of the key actually being played. The apparatus converts the actual keying pattern to a serial bit pattern which is then delayed by a desired number of bit positions. The delayed serial bit pattern is then converted back to a keying pattern to actuate the tone generator of the instrument.