| 摘要 |
<p>An apparatus for providing sound in vehicles (10) which comprises a receiving means for radio-frequency waves with frequency selection and an antenna (11) connected to said receiving means. The apparatus comprises moreover an operating means located in the vehicle close to the driver's seat including a power amplifier (15) with controls for sound adjustment, and loudspeakers (15) connected to said power amplifier. Said radio receiving means is divided into a master unit (14) close to the driver's seat in the vehicle, and a slave unit (12) which is located together with the antenna (11) remotely from said master unit (14). Said slave unit (12) comprises a circuit (16) controlled from said master unit for selecting a desired transmitter frequency and a circuit (19) for converting the selected signal into a signal of intermediate frequency with mainly a constant frequency. Said master unit comprises a detector, a pre-amplifier and said power amplifier along with controls for adjusting the receiver.</p> |
