TELEPHONE A PIECES DE MONNAIE

摘要

For a further payment request display in a payphone which is provided independently of the call duration for one charge unit a pre-defined time A before the credit is used up in telephone networks with automatic billing, an end time T is calculated with the aid of a microprocessor which is available to the caller up until the credit is used up and, with the aid of the end time T, a remaining time T-A is defined, at the end of which the further payment request signal is activated. The end time T is calculated according to the equation T = RG DIVIDED TW. t, RG representing the remaining credit, TW the charge pulse value and t the charge pulse cycle. The remaining time T-A is effective when the end time T