| 摘要 |
A device at TV surveillance comprises TV cameras (1, 2, ...), a video tape recorder (10), a switch device for sorting and transmitting the video signals of the different TV camera to the video tape recorder and a supply device for supplying a drive voltage and a synchronizing signal to each TV camera in the same conduit as the video signals are transmitted from each TV camera. The device has a video guard against the lack of a video signal from any TV camera or that the lens of any TV camera is covered and a synchronizing device for the video tape recorder for any possibly non-functioning TV camera. The switch device, the supply device, the video guard and the synchronizing device are all gathered in a recording unit (9). In this unit there is also a device for allowing the supply to a TV monitor (11) of a video signal from at least one TV camera, at the same time as recording by means of the video tape recorder occurs. |
