Patent ID: 6625423
Filing Date: 2003-09-23
Classification: H04M,H04W

Abstract:
A control device for answering an incoming call of a mobile phone by a phone set coupled to a pair of subscriber lines of a public telecom network, the mobile phone being provided with two earphone connecting lines and two microphone connecting lines for outputting an audio signal of the mobile phone, comprising:a central processing unit; a communication loop switching circuit having a pair of output lines coupled to the subscriber lines and a pair of phone set connecting lines coupled to the phone set, capable of establishing a communication loop for the phone set; a relay provided with two contact switches arranged in the communication loop switching circuit, controllable by the central processing unit; an incoming call detecting circuit having an input line connected to one of the earphone connecting lines and an output line coupled to the central processing unit, capable of generating an output signal to the central processing unit via the output line when detecting an incoming call; an audio signal converting circuit having four input lines connected to the earphone connecting lines and the microphone connecting lines of the mobile phone and two output lines, for converting the audio signal carried on the earphone connecting lines and the microphone connecting lines into an audio signal form adapted to be coupled to the phone set via the output lines; and a power supplying circuit connected between the communication loop switching circuit and the output lines of the audio signal converting circuit for supplying a power source to the audio signal converting circuit.