JPH0431815U

JPH0431815U -

Info

Publication number: JPH0431815U
Application number: JP7113790U
Authority: JP
Priority date: 1990-07-05
Filing date: 1990-07-05
Publication date: 1992-03-16

Description

[Brief explanation of the drawing]

第１図はこの考案に係る周波数偏移制御のＦＭ
変調回路の実施例を示す構成ブロツク図である。
第２図は従来例の構成ブロツク図である。１……エンコーダ、２……マイクロプロセツサ
、３……マイクロフオン、４……プリエンフアシ
ス回路、５……電子ボリユーウム、６……変調回
路、７……トーンエンコーダ。 Figure 1 shows the frequency shift control FM according to this invention.
FIG. 2 is a configuration block diagram showing an embodiment of a modulation circuit.
FIG. 2 is a block diagram of a conventional example. 1... Encoder, 2... Microprocessor, 3... Microphone, 4... Pre-emphasis circuit, 5... Electronic volume, 6... Modulation circuit, 7... Tone encoder.

Claims

[Claims for Utility Model Registration] An encoder that generates transmission frequency data and signaling data, a tone encoder that converts the signaling data into tone signals, a microprocessor that controls these data, and an audio signal from a microphone. A pre-emphasis circuit that applies pre-emphasis, and a modulation circuit that adds the output signal from the pre-emphasis circuit and the output signal from the tone encoder to a varicap via a level adjuster to perform frequency modulation, the output of the tone encoder and the output of the pre-emphasis circuit are combined. An electronic volume controlled by a microprocessor is installed in a level adjuster installed between the variable cap and the level controller, and the level is modulated with a constant frequency deviation commensurate with the transmission frequency and tone frequency set by the encoder. An FM modulation circuit for frequency shift control, characterized in that it is configured to control the output of an electronic volume as follows.