| 摘要 |
PURPOSE:To switch the supply of a signal automatically by connecting a switching circuit network having a semiconductor switching element between respective terminals connected to an external antenna, a tuner part of a receiver, an output terminal of an RF converter, and an antenna input circuit of another receiver. CONSTITUTION:The switching circuit network consisting of resistors R1-R5, capacitors C1-C5 and switching diodes D1-D5 is connected between terminals A, B, E, F, M, P. At the selection of a TV band, positive voltage is applied from a power supply switching device H to the terminals F, M, the diodes D3, D4, D5 are connected and a TV signal from an external anttena connected to a terminal P is supplied to a tuner part through the terminal E and a signal from an RF converter is passed from the terminal B to the terminal A and supplied to an antenna circuit of another receiver. In case of selecting FM and MW bands, negative voltage is applied to the terminal F, the diodes D1, D2 are connected and the TV signal is supplied to the other receiver through the terminal A. |
