| 摘要 |
<p>An apparatus for acquiring a modified baseband video signal from a CRT of a receiver includes a capacitive pickup (12) disposed on an external surface of a housing of the receiver and adjacent to a socket of the CRT, and two inductive pickups (14) having substantially mutually perpendicular axes disposed on the external surface of the housing (16) and spaced apart from the capacitive pickup. The capacitive pickup (12) senses a video signal of the receiver, and the inductive pickups (14) sense horizontal and vertical sync signals of the receiver. A horizontal sync component of the video signal is replaced in response to the horizontal sync signal sensed by the inductive pickups. A filter is arranged to filter out a band of frequencies centered about an integral multiple of a power line frequency. The capacitive pickup (12) has a capacitive pickup (12) plate and a capacitive shield plate which is located farther from the socket than the capacitive pickup plate. An axis of one of the two inductive pickups (14) is parallel to an axis of the CRT.</p> |
