JPS6093339U

JPS6093339U - Chuyuna

Info

Publication number: JPS6093339U
Application number: JP18359283U
Authority: JP
Inventors: 山中　栄一郎
Original assignee: 日本電気ホームエレクトロニクス株式会社
Priority date: 1983-11-30
Filing date: 1983-11-30
Publication date: 1985-06-26

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

第１図は、従来のＦＭチューナの構成図、第２図は、本
考案の一実施例の構成図、第３図ａおよびｂは、受信信
号の選択度特性曲線を示し、それｇぞれ、受信周波数を偏移させる前および偏移させた後を
示す。１・・・・・・電圧制御発振器（ＶＣＯ）、２・・・・
・・プログラム・デイバイダ、３・・・・・・ＣＰＵ、
　４・・・・・・操作部、５・・・・・・位相検出器、
６・・・・・・基準発振器、７・・・・・・ループフィ
ルタ（ＬＰＦ）、１０・・・・・・位相固定閉ループ（
ＰＬＬ）回路、１１・・・・・・周波数保持回路、１２
・・・・・・周波数偏移回路、２０・・・・・・アンテ
ナ、２１・・・・・・高周波増幅回路（ＲＦアンプ）、
２２・・間層波数混合回路（ミキサ）、２３・・・・・
・中間周波数増幅回路（ＩＦ’アンプ）、ａ、ｂ・・・
・・・スイッチ、ｆｏ・・・・・・発振周波数、ｆ、・
・・・・・基準周波数、ＳＬ・・・・・・位相固定信号
、ｖｃ・・・・・・直流制御電圧。Fig. 1 is a block diagram of a conventional FM tuner, Fig. 2 is a block diagram of an embodiment of the present invention, and Figs. 3 a and b show selectivity characteristic curves of received signals. , before and after shifting the receiving frequency. 1... Voltage controlled oscillator (VCO), 2...
...Program divider, 3...CPU,
4... Operation unit, 5... Phase detector,
6... Reference oscillator, 7... Loop filter (LPF), 10... Phase locked closed loop (
PLL) circuit, 11... Frequency holding circuit, 12
... Frequency shift circuit, 20 ... Antenna, 21 ... High frequency amplification circuit (RF amplifier),
22... Interlayer wave number mixing circuit (mixer), 23...
・Intermediate frequency amplifier circuit (IF' amplifier), a, b...
...Switch, fo...Oscillation frequency, f,...
...Reference frequency, SL...Phase fixed signal, vc...DC control voltage.

Claims

[Scope of utility model registration request]

In a tuner using a phase-locked closed loop circuit having a voltage-controlled oscillator as a local oscillation circuit, a frequency holding circuit is connected to the next stage of the voltage-controlled oscillator and holds the oscillation frequency at that time by a phase-locked signal of the phase-locked closed-loop circuit. and a frequency shift circuit that applies a DC control voltage to the voltage controlled oscillator to shift the oscillation frequency.