Abstract: In example embodiments, an apparatus includes a microphone, an emitter follower stage having an input coupled to the microphone, and an amplifier stage coupled to an output of the emitter follower stage. The amplifier stage is powered by a positive voltage regulator and a negative voltage regulator. In some embodiments, the microphone and the emitter follower stage are both referenced to a ground connection and are both biased by the positive voltage regulator. The output of the emitter follower stage may have an impedance that is an order of magnitude less than an impedance of the microphone. In some embodiments, the apparatus may be used to detect ultrasonic signals, such as those emitted by animals such as bats, rodents, and pest insects.

Abstract: Example embodiments include an apparatus comprising a first printed circuit board (PCB) having an AC-DC power supply thereon and a second PCB having a processor thereon. The first and second BPBs are substantially parallel to one another. A first thermal barrier extends between the first and second PCB. The processor and the power supply are both on a first side of the first thermal barrier. A chamber on a second side of the first thermal barrier opposite the first side. The chamber is at least partly enclosed by a second thermal barrier and has at least one opening for fluid communication with an ambient environment. A temperature sensor is provided in the chamber. In some embodiments, an LED is provided on one of the PCBs, and a light-reflecting silkscreened pattern is provided on the PCB near the LED to increase light output of the apparatus.

Abstract: Example embodiments include an apparatus with a buffer amplifier having an output node. A first switchable unidirectional current path is provided between the output node and a capacitor, the first path allowing current flow from the capacitor to the output node. A second switchable unidirectional current path is provided between the output node and the capacitor, the second path allowing current flow from the output node to the capacitor. Comparator circuitry is provided that operates to open the first path if the capacitor voltage is above an upper threshold and to open the second path if the capacitor voltage is below a lower threshold. The capacitor voltage may be read by an analog-to-digital converter.

Abstract: Example embodiments include a mounting system and method for a sensor node or other electrical or electronic device. An apparatus according to some embodiments includes a housing having a perimeter and a rear surface, a set of power plug prongs extending from the rear surface of the housing, and a bracket releasably engageable with the rear surface of the housing, the bracket having at least one flange that extends beyond the perimeter of the housing when the bracket is engaged with the rear surface. In some embodiments, at least one of the flanges includes a frangible region allowing for removal of at least a portion of the respective flange.

Abstract: Example embodiments include an apparatus with a buffer amplifier having an output node. A first switchable unidirectional current path is provided between the output node and a capacitor, the first path allowing current flow from the capacitor to the output node. A second switchable unidirectional current path is provided between the output node and the capacitor, the second path allowing current flow from the output node to the capacitor. Comparator circuitry is provided that operates to open the first path if the capacitor voltage is above an upper threshold and to open the second path if the capacitor voltage is below a lower threshold. The capacitor voltage may be read by an analog-to-digital converter.