Portable radio communication device having signal processing circuit with presetting function

Claim 1

A portable radio communication device comprising: (a) battery means; (b) voltage converter means connected to said battery means for converting the voltage of said battery means to another voltage; (c) processing circuit means, having a presetting terminal and a power supply terminal to which said other voltage is supplied, for detecting and processing received signals; (d) presetting circuit means provided between the output of said volage converter means and said presetting terminal for setting said processing circuit means in an initial state in response to said other voltage; said presetting circuit having at least one element which is chargeable and dischargeable; and (e) power supply switch means having a first terminal connected to said battery means, a second terminal connected to a reference potential point, a third terminal connected to the input of said presetting circuit either directly or by way of a low impedance means and a connecting means for selectively connecting pairs of said terminals; the voltage of said battery means being supplied in response to a connection of said first and second terminals, and the voltage supply from said battery means being stopped and a discharge time of said element in said presetting circuit being set at a sufficiently low value so that said processing means is securely maintained in said initial state when battery voltage is supplied initially or after prior battery voltage stoppage in response to a connection of said second and third terminals.