Hitachi, Ltd.

Tadashi Onishi

Minoru Nagata

Nobuo Hamamoto

Kenichi Mizuishi

Tatsundo Suzuki

Yosuke Tyojamori

Katsutaka Kimura

Toshio Sasaki

Toshiaki Masuhara

Masatoshi Ohtake

Naoki Ozawa

Katsuro Sasaki

Hidehito Obayashi

Kiyoshi Aiki

Kazuhiro Kondo

Isamu Orita

Hiroshi Kishida

Hisashi Horikoshi

In a digital information system for realizing the sale of information or the like having a commercial value in the form of a digital signal, and an audio processor, and signal processor suitably used with the system, when a digital signal is received/delivered, a digital signal source is connected directly to a player for receiving and storing a specified information, which is reproduced by the player independently. A voice interval of a digital audio signal is processed to realize the slow and fast playback. The system includes a data compressor and a data extender of simple configuration. The value of the digital signal received/delivered can be exhibited directly. A selling system is constructed easily, and the player is simple in configuration and easy to operate by anyone. The fast and slow playback are possible without deteriorating the sound quality, and ripples can be greatly reduced against the digital input signal, thereby making possible a faithful data compression of an acoustic signal or the like by a simple configuration. The self-diagnosis function permits the use of a defective memory chip, thereby leading to a very economical system.

Digital information system, digital audio signal processor and signal converter

A radio paging system with voice transfer function for transmitting a voice message input from an ordinary push-button telephone set to a small-sized receive-only unsophisticated radio pager. A paging station is provided to transmit by radio the message from a telephone network to the radio pager as follows: voice information constituting the message is first converted from analog to digital format, compressed, stored in memory, and scrambled by a privacy function part for transmission. The radio pager in turn demodulates the received information, stores it in memory, retrieves a necessary message therefrom as designated, descrambles the designated message from scrambled state, expands the message from compressed state, and outputs the message as an audible output. In this manner, the user carrying the radio pager is able to get the message from the caller without the risk of being tapped by a third party.

Radio paging system with voice transfer function and radio pager

Growing community of inventors

Hachioji, Japan

Tadashi Onishi