| 摘要 |
PURPOSE:To obtain easily the tuning voltage of each channel which is perfectly controlled for its tracking, by writing previously the signal selecting tuning voltage and the local oscillating tuning voltage of all channels to a nonvolatile memory. CONSTITUTION:The signal selecting tuning voltage and the local oscillating tuning voltage of all channels are stored previously to a nonvolatile memory M1 for each of a VHF high band, a VHF low band and a UHF band. Then the contents of a specific address of a nonvolatile memory M1 are read and delivered in response to the channel designating input to a central processing part CPU. These delivered signals are applied to a D/A converter switch circuit DS, and each tuning voltage corresponding to the contents of the memory M1 is applied to a tuner part TU. At the same time, the U-V switching voltage and the high- low switching are applied to voltage applying terminals BU, BV and BS from a switching circuit part of the circuit DS. In such a way, the designated channel is selected. |
