Abstract: An active direct box comprising an electronic circuit for receiving an unbalanced, high-impedance format audio signal input, and for providing a balanced, low-impedance audio signal output, compatible with common audio system components such as audio consoles and recorders. The direct box circuit receives power from a phantom power source supplied by the audio system component to which the direct box is connected. The phantom power source is isolated, and used to provide a bias supply to a pair of JFET operational amplifiers in the electronic circuit which convert the audio signals, and which provide for both signal gain and signal reduction. A negative feedback system is further employed to covert the input audio signals to a low-impedance format with a minimal introduction of signal distortion.

Abstract: A device for disinfecting food stored in a refrigerated compartment, utilizing radiation emitted in the ultraviolet wavelengths between 200 and 300 nanometers emitted by a lamp. The lamp is installed on an upper surface of an enclosed refrigerator compartment lined with a reflective lining adapted to reflect radiation in the ultraviolet wavelengths. A raised grill is provided within the enclosed compartment for the placement of food products for disinfecting above a lower surface of the compartment, permitting reflected ultraviolet radiation to impact the underside of the food products. A switch triggered by the opening and closing of a door on the refrigerator, and a timer activated by the switch, activate the ultraviolet lamp after a predetermined period has elapsed from closure of the refrigerator door.

Abstract: An audio amplification circuit includes a ganged pair of logarithmic potentiometers, each potentiometer of the pair having an input terminal, an output terminal, and a wiper terminal. The input terminals of each potentiometer are adapted for connection to an audio input signal from an audio device such as a microphone. A preamplifier stage having an input is connected to the wiper terminals of both logarithmic potentiometers. An amplification stage has a matched pair of operational amplifiers with each operational amplifier having an input connected to the output of the preamplifier stage. Each operational amplifier has a feedback loop which includes the resistance of at least one of the logarithmic potentiometers between the output terminal and the wiper terminal of said logarithmic potentiometer. The outputs of the matched pair of operational amplifiers constitute the outputs of the amplification stage. The outputs may be daisy-chained together, and a floating output stage is also provided.