FREE PUBLIC TELEPHONE SYSTEM BY LISTENING TO COMMERCIAL BROADCAST

摘要

PURPOSE: A free public telephone system enables a user to use a public telephone free if he/she listens to a commercial broadcast for a predetermined time. CONSTITUTION: If a user inserts a public telephone card for listening to a commercial broadcast or touches the buttons which a telephone service proprietor presets, a public telephone(100) outputs a control signal for outputting the commercial broadcast through a receiver(101) for a predetermined time, and becomes a waiting for call state so that the user can use the public telephone free after the commercial broadcast is finished. An exchange(200) outputs the pre-stored commercial broadcast to the public telephone if the control signal of that the user inserts a public telephone card for listening to a commercial broadcast or touches the preset buttons is inputted from the public telephone. After the commercial broadcast is finished, the exchange controls the connection with other exchange so that the user can call a person to be wanted. Therefore, the user can use the public telephone free. Also, both advertiser and telephone service proprietor can acquire profits.