Abstract: A head set speaker and stereo radio playing device exhibits improved harmonics and acoustic fidelity. A resilient and flexible headpiece is sized to fit behind the head of the user. Right and left device enclosures are carried by the ends of the headpiece, and are aerodynamic shaped to minimize wind whistle which may result when the head set is worn while moving rapidly. Right and left behind the ear flanges extend downwardly from a position adjacent to the ends of the headpiece, and aid in the positioning of the right and left ear device enclosures. In a typical application, the device enclosures are positioned immediately forward of the user's ears, allowing ambient sound to be heard. A speaker assembly and a removable battery assembly are carried within each device enclosure. The speakers are oriented within the device enclosures with the speaker magnet directed to, and in contact with, the head of the listener. This achieves two interrelated and significant structural and electronic advantages.

Abstract: An amplifier circuit (10) having a rotating input stage has a switching network (12) connected to an input (14). A number of parallel transconductance gain stages (16) are connected to the switching network (12). An auto-zeroing circuit (18) is connected to the switching network (12). A second transconductance gain stage (20) is connected to the parallel transconductance gain stages (16).

Abstract: A power stealing circuit to charge a capacitor includes a passive electrical power channel. The passive electrical power channel has an input connected to an input signal and an output designed to be connected to the capacitor. An active electrical power channel is powered by the capacitor. The active electrical power channel has an input connected to the input signal and an output connected to the capacitor.

Abstract: A low-corner frequency high pass filter circuit (10) includes an operational amplifier (12). The operational amplifier (12) has an inverting input (14) and a non-inverting input (24). A series capacitor (26) has a first end connected to the non-inverting input (24) of the operational amplifier (12). A second end of the series capacitor (26) is connected to an input signal (28). A low gain amplifier (30) has an input connected to an output (22) of the operational amplifier (12) and has an output (32) connected to the non-inverting input (24) of the operational amplifier (12). The low gain amplifier (30) performs the function of large value resistor.

Abstract: A parasitically compensated resistor (50) for integrated circuits includes a substrate (52). A polysilicon resistor (54) is formed in the substrate (52). The polysilicon resistor (54) has a first end connected to a first lead (56) and a second end connected to a second lead (58). A conductive layer (62) is capacitively connected to the polysilicon resistor (54).

Abstract: An amplifier circuit (10) having a rotating input stage has a switching network (12) connected to an input (14). A number of parallel transconductance gain stages (16) are connected to the switching network (12). An auto-zeroing circuit (18) is connected to the switching network (12). A second transconductance gain stage (20) is connected to the parallel transconductance gain stages (16).

Abstract: An amplifier circuit (20) for a photodetector includes a transconductance variable gain stage (32). The transconductance variable gain stage (32) has an input (34) capable of connecting to the photodetector and an output (40). A transconductance gain stage (44) has an input (42) connected to the output (40) of the transconductance variable gain stage (32). A feedback resistor (46) is connected between an output (48) of the transconductance gain stage (44) and the input (42) of the transconductance gain stage (44).

Abstract: A root-watering system which is attachable to a valved water supply. The system includes a plastic tube with a threaded coupling for attachment to a spray nozzle. A stake connects to the opposite end of the tube and may be inserted into the soil using a foot pedal to bring a stream-directing slot into the vicinity of the plant's roots. A V-shaped barrier protects the slot from being packed with soil.