JPS59121947U

JPS59121947U - Tuner input switching device

Info

Publication number: JPS59121947U
Application number: JP1577383U
Authority: JP
Inventors: 杉本　共延
Original assignee: 日本電気ホームエレクトロニクス株式会社
Priority date: 1983-02-04
Filing date: 1983-02-04
Publication date: 1984-08-16

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ＵＨＦチューナを結合するＶＨＦチュー
ナの入力段回路図、第２図は第１図のＵＨＦチューナの
結合による等価回路図、第３図は本考案のチューナ入力
切換装置の要部回路図、第４図は第３図におけるダンピ
ング抵抗値とトラップ妨害の関係を示す特性図、及び第
５図は異な゛　るダンピング抵抗を用いた周波数レスポ
ンス特性図である。１・・・・・・ＵＨＦチューナ、２・・・・・・固定側
チューナ回路、３・・・・・・シールドケーブル、４・
・・・・・回動側ターレット体、５・・・・・・ＵＨＦ
中継用セグメント、６・・・・・・ＶＨＦ同調用セグメ
ント、７・・・・・・増幅素子（トランジスタ）、８・
・・・・・ＵＩＦ入力端子、１０・・・・・・■Ｆ同調
フィルタ、１６・・・・・・入力コイル、２０・・・・
・・トラップ回路、２１・・・・・・抵抗。Figure 1 is an input stage circuit diagram of a VHF tuner that combines a conventional UHF tuner, Figure 2 is an equivalent circuit diagram of the UHF tuner of Figure 1 combined, and Figure 3 is the main part of the tuner input switching device of the present invention. The circuit diagram, FIG. 4 is a characteristic diagram showing the relationship between the damping resistance value and trap disturbance in FIG. 3, and FIG. 5 is a frequency response characteristic diagram using different damping resistances. 1...UHF tuner, 2...Fixed side tuner circuit, 3...Shield cable, 4...
...Rotating side turret body, 5...UHF
Relay segment, 6... VHF tuning segment, 7... Amplifying element (transistor), 8...
...UIF input terminal, 10...■F tuning filter, 16...Input coil, 20...
...Trap circuit, 21...Resistance.

Claims

[Scope of utility model registration request]

A rotating turret body having a UIF relay segment and a plurality of VHF tuning segments, an RF amplification element, and a UIF
A fixed side tuner circuit having a UIF input circuit section including UIF input terminals supplied by the IF ratio output coupling cable of the HF tuner and an IF tuning filter coupled between these input terminals and the RF amplification element, and a rotating side turret. switch means for selectively connecting between each segment contact group of the body and the terminal group of the fixed side tuner circuit, and the segment of the desired channel is connected to the tuner circuit by the circuit of the turret body.
In a turret-type VHF tuner that selectively connects to a channel for channel selection, when the tuning segment of a specific channel is selected, a signal is connected between the UIF input terminal and the high-frequency ground point via this tuning segment. A tuner input switching device characterized in that a resistor selected in the range of 4 to 8 ohms is inserted to prevent trap interference.