Abstract: An electronic circuit comprising, in cascade, a two-port having an input terminal and an output terminal, and a controllable transfer circuit comprising an input terminal, an output terminal, and an external control terminal, there being provided a switching means having a parent contact and two switching contacts. The parent contact is connected to the control terminal, the first switching contact to the output terminal of the two-port, and the second switching contact to the input terminal of the two-port, and a through-connection is provided between the output terminal of the two-port and the input terminal of the controllable transfer circuit.