公开(公告)号：US3866112A

公开(公告)日：1975-02-11

申请号：US44135574

申请日：1974-02-11

申请人： HITACHI LTD

发明人： YOKOYAMA KANJI ,  MATSUO HIROYUKI

IPC分类号： H03J5/02 ,  H03K17/735 ,  H04N5/44 ,  H03J5/04

CPC分类号： H03K17/735 ,  H03J5/0218

摘要： A channel selecting apparatus for a television receiver including channel selecting buttons, channel selecting signal amplifying transistors, switching circuits for switching the tuning voltage, voltage regulators for adjusting the voltage to be supplied to an electronic tuner, and an electronic tuner and characterized by a circuit for deriving a part of a channel selecting signal and a malfunction preventing circuit which stores the derived channel selecting signal and, after a predetermined time period, i.e., after the switching operation of the switching circuit has completed, produces a voltage sufficient for cutting off the channel selecting signal amplifying transistors which is applied to the signal amplifying transistors in a reversely biasing manner.

摘要翻译： 一种用于电视接收机的频道选择装置，包括频道选择按钮，频道选择信号放大晶体管，用于切换调谐电压的开关电路，用于调节要提供给电子调谐器的电压的调压器，以及电子调谐器，其特征在于电路 用于导出信道选择信号的一部分和存储导出信道选择信号的故障防止电路，并且在预定时间段之后，即在切换电路的切换操作完成之后，产生足以切断 以反向偏置的方式施加到信号放大晶体管的信道选择信号放大晶体管。