Apparatus and methods are described, including a method for transmission of power and data during a plurality of consecutive time intervals. During a power-transmission portion of each of the plurality of consecutive time intervals, a power signal, in which no data is encoded, is transmitted. During a power-and-data-transmission portion of each of the plurality of consecutive time intervals, a power-and-data signal, in which is encoded a single bit, is transmitted. The power-and-data signal includes: (a) a high-level power-and-data signal portion, and (b) a low-level power-and-data signal portion. Other applications are also described.