Patents Assigned to Dimango Products Inc.
  • Patent number: 5612666
    Abstract: A wireless audible indication system comprising a transmitter and a receiver. An embodiment of the transmitter includes a crystal oscillator which produces a signal having a predetermined audio frequency. A duty cycle limiting circuit limits the duty cycle of the oscillator signal to be less than 25%. The limited duty cycle signal is applied to a radio frequency oscillator to produce an amplitude modulated radio frequency signal. An embodiment of the receiver includes a superregenerative detector which provides wide band detection of transmissions about a carrier frequency. A signal processing circuit formed by a cascade of a crystal filter stage, an amplifier/comparator stage, and a detector stage, processes the signal from the superregenerative detector. A sound generator integrated circuit, which generates an audible signal indicative of reception of a transmitted signal, is coupled to the signal processing circuit.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: March 18, 1997
    Assignee: Dimango Products Inc.
    Inventor: Thomas G. Xydis