| 摘要 |
PURPOSE:To eliminate the effect of dispersion in a receiving channel number and manufacture of an electronic tuner, by constituting a fine tuning state of a channel selecting device in a short storage bit number so as to decrease the number of bits of a storage device and to simplify the circuit constitution. CONSTITUTION:The channel selecting device is provided with a channel selection control circuit and the electronic tuner 22, the tuning voltage applied to the tuner 22 is digitized and the tuning voltage corresponding to the selected channel number is stored in a nonvolatile memory 3. The data stored in this memory 3 is read at the 1st selector 4 at the channel selection and applied to the 2nd shift register 7. This channel selecting device is provided with a fine operating switch 12, a fine tuning circuit 13, the 1st reversible counter 14, an operating circuit 8, a fine tuning operating signal generating circuit 16, and the 2nd reversible counter 20 and the like. Further, the fine tuning state of the channel selecting device is taken as a short storage bit number, the number of bits of the memory 3 is decreased, the effect of the dispersion in the receiving channel number and the manufacture of the tuner 22 is eliminated and the constitution of the channel selecting device is simplified. |
