PURPOSE: To make possible a re-calling process after the on-hook operation of a public telephone set user without reinserting a prepaid card(PC) by temporary stopping the PC from being returned for a period, holding the balance of the PC and performing the re-calling process when the off-hook operation is performed in the period, and returning the PC after the period.

CONSTITUTION: If a telephone number is misdialed in calling operation or if re-caging operation is performed even after a current telephone call ends by using the PC which is already inserted into a PC control part 5, the user lowers a hook 8 momentarily and lowers the hook 8, and then a hook switch 6 is opened. Then a hook timing control part 9 detects the hooking. The control part immediately opens a line switch 2 and closes the switch 2 a previously set time later. At this time, the hook 8 is raised, so a circuit part 3 repeats normal calling operation even at the time of the re-calling operation. The control circuit 9, on the other hand, monitors the closure of the switch 6 and delays output to the control part 4 by a previously set period. The control part 9 once detecting the closure of the switch 6 in the set period does not perform the output to the control part 4 and allows the re-calling operation.