Abstract: Some embodiments provide for an inspiratory limb for a breathing circuit that includes a first segment that comprises a first heater wire circuit and a second segment that comprises a second heater wire circuit. The inspiratory limb can include an intermediate connector that includes a connection circuit that electrically couples the first heater wire circuit to the second heater wire circuit. The inspiratory limb can be configured to operate in two modes wherein, in a first mode, electrical power passes through the first electrical connection to provide power to the first heater wire circuit without providing power to the second heater wire circuit, and in a second mode, electrical power pass through the first electrical connection to provide power to both the first heater wire circuit and the second heater wire circuit.

Abstract: A stereo inhibit circuit adaptable for use in an FM stereo radio having a stereo indicating light is disclosed. A level detector and a mute circuit develop a mute signal which is related to the amount of signal noise at the output of an FM detector. This mute signal is used to inhibit a stereo switch that controls the stereo indicating light while permitting the creation of audible signals by a stereo demodulator and a pair of speakers. Thus the stereo inhibit circuit permits the creation of an audible hiss and positively prevents any flickering of the stereo indicating light when the FM radio is not tuned to a station.