JPH0351523U

JPH0351523U -

Info

Publication number: JPH0351523U
Application number: JP11254689U
Authority: JP
Priority date: 1989-09-26
Filing date: 1989-09-26
Publication date: 1991-05-20

Description

[Brief explanation of drawings]

第１図はコードレス電話機のＲＦユニツトと本
考案の実施例である調整装置のブロツク図、第２
図は同調回路の一例を示す回路図である。２−ａ……信号発生器、２−ｂ……第１局部発
振器、２−ｃ……同調回路、、２−ｄ……第１Ｉ
Ｆフイルタ、２−ｅ……ＩＦアンプ、２−ｆ……
第２局部発振器、２−ｇ……第２ＩＦミキサ、２
−ｈ……第２ＩＦフイルタ、２−ｉ……復調器、
２−ｊ……オーデイオアンプ、２−ｋ……スピー
カ、２−ｌ……選択フイルタ、２−ｍ……整流平
滑回路、２−ｎ……反転増幅器、２−ｏ……可変
直流電圧源、２−ｐ……制御ユニツト、２−ｑ…
…Ａ／Ｄ変換器、２−ｒ……ＲＦ増幅器、２−ｓ
……Ｄ／Ａ変換器、２−ｔ……ＲＯＭ、２−ｕ…
…制御ユニツト搭載位置、２−ｖ……オフセツト
調整抵抗、Ｌ２……同調コイル、Ｄ１……電圧制
御可変容量素子、Ｑ２……ミキサトランジスタ。 Figure 1 is a block diagram of the RF unit of a cordless telephone and the adjustment device that is an embodiment of the present invention;
The figure is a circuit diagram showing an example of a tuning circuit. 2-a... Signal generator, 2-b... First local oscillator, 2-c... Tuning circuit, 2-d... First I
F filter, 2-e...IF amplifier, 2-f...
Second local oscillator, 2-g...Second IF mixer, 2
-h...Second IF filter, 2-i...Demodulator,
2-j... Audio amplifier, 2-k... Speaker, 2-l... Selection filter, 2-m... Rectifying and smoothing circuit, 2-n... Inverting amplifier, 2-o... Variable DC voltage source, 2-p...control unit, 2-q...
...A/D converter, 2-r...RF amplifier, 2-s
...D/A converter, 2-t...ROM, 2-u...
...control unit mounting position, 2-v...offset adjustment resistor, L2...tuning coil, D1...voltage controlled variable capacitance element, Q2...mixer transistor.

Claims

[Claims for Utility Model Registration] In a device for setting the tuning frequency of a single-tuned circuit to a predetermined frequency using a voltage-controlled variable capacitance element and means for storing its control voltage, the single-tuned circuit is provided with a standard signal of the predetermined frequency. means for inputting a distortion component from the output of the single tuned circuit; means for changing the control voltage of the capacitive element so that the output of the distortion component extraction means is minimized; and when the distortion component is at its minimum. A single tuned circuit adjusting device comprising: means for recording a control voltage in the storage means;