Abstract: A receptacle that can detect the insertion and extraction of a plug includes: a receptacle shell having formed therein a plug insertion port into which the plug is inserted and from which the plug is extracted; a receptacle body provided inside the receptacle shell; a movable contact that is installed at a base portion of the receptacle body, the base portion faces a distal end of the plug inserted into the plug insertion port, and that is deformed elastically when pushed by the plug; and an immovable contact that is installed at the base portion, is normally spaced from the movable contact, and comes into contact with the movable contact when the movable contact is pushed by the plug and elastically deformed. The receptacle that can conform to the HDMI standard can be realized without adding any modification to main components relating to mating with a plug.

Abstract: A drop-out detecting apparatus comprises an amplitude detecting circuit supplied with a high frequency video signal reproduced from a record medium, a first smoothing circuit supplied with a detected output of the amplitude detecting circuit and having a short time constant so that it produces an output having a drop-out, a second smoothing circuit supplied with the detected output of the amplitude detecting circuit and having a long time constant so that it produces an output having no drop-out, a detecting circuit for level-comparing a smoothed output of the second smoothing circuit and a first reference level to produce an output of large or small level, and a comparing circuit for level-comparing a smoothed output of the first smoothing circuit and a second reference level provided by attenuating the detected output of the detecting circuit by a predetermined attenuating ratio, wherein the comparing circuit derives a drop-out detecting signal.