JPS58178744U

JPS58178744U - Prescaler interface circuit

Info

Publication number: JPS58178744U
Application number: JP7624082U
Authority: JP
Inventors: 正雄高島
Original assignee: 株式会社東芝
Priority date: 1982-05-26
Filing date: 1982-05-26
Publication date: 1983-11-30

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 the drawing]

第１図はヅンセサイザ選局回路を説明するための回路図
、第２図は上記選局回路と電子同調チューナとを結合す
る従来のプリスケーラ゛・インタフェース回路を示す回
路図、第３図は上記インターフェース回路の必要とする
周波数特性を示す特性図、第４図はチューナのＡＧＣ電
圧に対する利得、制御の一例を示すチューナＡＧＣ特性
を示す特性図、第５図は入力電界に対するチューナＡＧ
Ｃ特性とＩＦＡＧＣ特性を比較して示す入力対ＡＧＣ電
圧の特性図、第６図は受信チャンネルの切換えに際しチ
ューナＡＧＣ電圧が変化する様子を示すＡＧＣ電圧の変
化図、第７図は本考案の一実施例を示す回路図である。２１・・・チューナ、２２・・・電圧制御発振器、２６
・・・選局回路、２７・・・プリスケーラ、２８・・・
利得制御手段（電圧制御回路）、２９・・・電源電圧供
給端子、３０・・・ＡＧＣ電圧給電端子、３１・・・制
御信号印加端子、３２・・・トランジスタ、３３．　３
４゜３７・・・抵抗、３５・・・チューナ利得制御端子
。Fig. 1 is a circuit diagram for explaining a synthesizer tuning circuit, Fig. 2 is a circuit diagram showing a conventional prescaler interface circuit that connects the above-mentioned tuning circuit and an electronic tuning tuner, and Fig. 3 is a circuit diagram showing the above-mentioned interface. A characteristic diagram showing the frequency characteristics required by the circuit. Fig. 4 is a characteristic diagram showing the tuner AGC characteristics showing an example of gain and control for the AGC voltage of the tuner. Fig. 5 is a characteristic diagram showing the tuner AGC characteristic for the input electric field.
A characteristic diagram of input vs. AGC voltage showing a comparison of C characteristics and IFAGC characteristics, FIG. 6 is a change diagram of AGC voltage showing how the tuner AGC voltage changes when switching reception channels, and FIG. FIG. 2 is a circuit diagram showing an example. 21... Tuner, 22... Voltage controlled oscillator, 26
... Tuning circuit, 27... Prescaler, 28...
Gain control means (voltage control circuit), 29... power supply voltage supply terminal, 30... AGC voltage supply terminal, 31... control signal application terminal, 32... transistor, 33. 3
4゜37...Resistor, 35...Tuner gain control terminal.

Claims

[Scope of utility model registration request]

In a control bag that combines a channel selection circuit and an electronic tuning tuner using a prescaler to maintain the local oscillation frequency at a normal frequency, it is possible to respond to human operations such as changes in the electric field of the receiving channel. 1. A prescaler interface circuit comprising: a gain control means for controlling the amplification gain of said electronic tuning tuner based on a control signal generated by said prescaler;