For dispensing volumes of liquids, a hinged septum has a flap inclined with respect to the longitudinal axis of a liquid channel. The bandpass filter is applied to the photodetector signal to determine a tissue perfusion measurement from the filtered signal. The signaling information having the fixed number of bits includes information about a number of Radio Frequency channels, and the signaling information having the variable number of bits includes information representing a frequency for each of the RF channels, respectively. The originating MSC system then transmits a repeat dialing indicator to the HLR system for the called party.