Abstract: A multiple output transformer network for a high-fidelity sound reproducing system which includes a high-frequency speaker and a low-frequency speaker, first and second audio output autotransformers, a high-frequency bandpass filter coupling the first autotransformer to the high-frequency speaker, and a low-frequency bandpass filter coupling the second autotransformer to the second speaker, all of the foregoing components being mounted in a remote speaker unit. The winding of the first autotransformer is connected to the output amplifier of the sound reproducing equipment by a first extension lead, and to ground; and the winding of the second autotransformer is connected to the output amplifier of the sound reproducing equipment by a second extension lead and to ground; and the high-frequency and low-frequency bandpass filters are respectively connected to center taps on the windings of the first and second autotransformers.

Abstract: A multiple output transformer network for a high-fidelity sound reproducing system which includes a high-frequency speaker and a low-frequency speaker, first and second output transformers, a high-frequency bandpass filter coupling the secondary of the first output transformer to the high-frequency speaker, and a low-frequency bandpass filter coupling the secondary of the second transformer to the second speaker, all mounted in a remote speaker unit. The primary windings of the transformers are connected to the output amplifier of the sound reproducing equipment by first and second extension leads. The output amplifier includes first and second triodes series connected across a source of unidirectional potential, and first and second capacitors coupling the extension leads to the common connection of the triodes.

Abstract: A defrost assembly for the evaporator of a refrigerator comprises a thin heating plate of thermally conductive material underlying the evaporator. An electric cord is mounted to an underside of the heating plate for heating the heating plate. A thermal insulating board underlies the heating plate. A thermally responsive cut-off terminates flow to the electric cord when the evaporator reaches a prescribed temperature. A rear portion of the heating plate forms a channel for draining-off melted water.

Abstract: A method of fingerprint verification includes determining a direction difference between a direction pattern of an input fingerprint and a direction pattern of a registered fingerprint and comparing the determined direction difference with predetermined upper and lower threshold values. The input and registered fingerprints are considered the same if the direction difference is lower than the lower threshold value, and the input and registered fingerprints are considered to be different if the direction difference is higher than the upper threshold value. If the direction different is between the upper and lower threshold values, minutiae of the input and registered fingerprints are extracted for verifying the input fingerprint. The extracting includes preprocessing of the input fingerprint image, uniboundary extraction of the input fingerprint minutiae, and restoration to eliminate pseudo-minutiae.