Abstract: Users of video telephones or multimedia terminals cannot determine whether ambient light conditions during a transmission to another terminal are always of good quality. Provision is made for an indication regarding the ambient light conditions during a telephone call, and control thereof. By means of a circuit arrangement including a photocell (F) to detect incident light, a signal (II) is formed, which corresponds to the ambient light conditions. The signal (II) is displayed together with a video signal (I), or is used for control purposes.

Abstract: An access device at a public communications terminal enables an authorized user to gain access, via a connecting device, to an integrated services digital communications network. The access device includes a connecting device (2) behind a protective member (4) which permits access only after a check of the user's access authorization and a test of the correct functioning of the connecting device.

Abstract: The present invention relates to a pushbutton switch assembly for use with telephone sets, having an integrated lock-down switch. With the aid of a rotatable trip cam of the lock-down switch, randomly one of several domes of a rubber-like switching mat of the pushbutton switch assembly can be actuated, so that certain operational conditions can be switched.