Communication terminal having means for controlling power transfer

A communication terminal which is coupled to a communication network via transmitting and receiving signal lines and a switching system, said communication terminal comprising:

• a power input line coupled to the transmitting and receiving signal lines;
• a power sink coupled to said power input line for supplying power from an output side thereof;
• switching means coupled to the output side of said power sink;
• a hook switch coupled to the output side of said power sink in parallel to said switching means;
• detection circuit means coupled to the receiving signal line for detecting a signal on the receiving signal line;
• state maintaining circuit means coupled to said switching means and said detection circuit means for closing said switching means and for maintaining said switching means in a closed state by carrying out a state maintaining operation when a signal is detected by said detection circuit means;
• and
• prohibit circuit means coupled to said detection circuit means for prohibiting a signal detection of said detection circuit means.