发明授权
- 专利标题: Electronic digital channel-selecting apparatus
- 专利标题(中): 电子数字通道选择装置
-
申请号: US12461申请日: 1979-02-15
-
公开(公告)号: US4262364A公开(公告)日: 1981-04-14
- 发明人: Masahiro Fujita
- 申请人: Masahiro Fujita
- 申请人地址: JPX Kawasaki
- 专利权人: Tokyo Shibaura Denki Kabushiki Kaisha
- 当前专利权人: Tokyo Shibaura Denki Kabushiki Kaisha
- 当前专利权人地址: JPX Kawasaki
- 优先权: JPX53-20832 19780227; JPX53-80855 19780705
- 主分类号: H03J5/02
- IPC分类号: H03J5/02 ; H03J7/06 ; H04B1/26
摘要:
An electronic digital channel-selecting apparatus wherein a digital signal corresponding to a selected television channel is read out of a digital memory to be converted into an analog tuning voltage by a digital-analog converter; and the analog tuning voltage is applied to a voltage-controlled tuner which in turn is made to tune with the selected television channel. An AFT circuit is coupled to the tuner to detect its tuning condition. When the tuner does not accurately tune with the selected television channel, AFT clock pulses are supplied to an AFT counter to correct the analog tuning voltage depending on varying count numbers in the AFT counter. A clock changer is provided to switch AFT clock pulses having different frequencies such that the AFT clock pulses are successively applied to the AFT counter in the decreasing order of their frequencies during the AFT control.
公开/授权文献
- USD357061S Extension for a swimming pool water return line 公开/授权日:1995-04-04
信息查询
IPC分类: