Abstract: A signal transmission system includes concentratedly arranged various kinds of electronic apparatus capable of transmitting information such as audio and/or video, and so forth. The system is provided with a main controller for controlling those apparatus and an auxiliary controller arranged in a plurality of chambers via cables so that information can be properly watched and heard through the above main controller. The system processes the transmission of information in a short time and also provides possibility of controlling even an electronic apparatus having no means for receiving control signals through wire by having the signals outputted in parallel or in series control signals for demanding transmission of information properly are fed to the various kinds of electronic apparatus from the auxiliary controller through the main controller.

Abstract: A magnetic head position control apparatus for driving the magnetic head of a disc recording apparatus toward or away from the recording surface of a magneto-optical disc to effect position control of the magnetic head detects changes in the distance between the magnetic head and the magneto-optical disc by detecting changes in the capacitance between a capacitance detection electrode mounted on the magnetic head and a surface of the magnetic disc and generates a voltage to control the position of the magnetic head for maintaining it at a constant predetermined distance from the magneto-optical disc. Stray capacitance between the disc and the disc recording apparatus is based on the size of the disc, which is either detected directly or obtained from pre-recorded data on the disc, and is compensated by adding a bias voltage to the voltage generated using the capacitance detection electrode to provide further control of the position of the magnetic head.

Abstract: A magnetic head position control apparatus for driving the magnetic head of a disk recording apparatus toward or away from the recording surface of a magneto-optical disk to effect position control of the magnetic head. Changes in the distance between the magnetic head and the magneto-optical disk are detected from changes in capacitance between a capacitance detection electrode mounted on the magnetic head and a surface of the magneto-optical disk. An oscillator circuit connected to the capacitance detection electrode varies its oscillation frequency in response to changes in capacitance and detects such frequency variations and controls the position of the magnetic head for maintaining it at a constant predetermined distance from the magneto-optical disk.