Abstract: The present invention relates to an oscillator circuit. In the oscillator circuit, the level of the output signal is monitored and compared to a desired reference level. An error signal is then generated and used to modify the feedback so that the negative resistance of the active device presented to the resonator exactly equals the magnitude of the positive resistance of the resonator without having to rely upon saturation in the active device and for very linear operation of the device such that over the full swing of the output, the negative impedance presented to the resonator remain extremely constant—thus reducing the sensitivity of the oscillator to any noise present.

Abstract: A utility shutoff marking system includes a first marking sign, a second marking sign, and hangers. The first marking is sign is for mounting at the location of electrical shutoff, and has a printed indicia representing the electrical shutoff, the marking sign being made of a rugged material resistant to deterioration. The second marking sign is for mounting at the location of the main water shutoff, and also has printed indicia representing the main water shutoff, the marking sign being made of a rugged material resistant to deterioration. The hangers are for mounting the first marking sign and the second marking sign at the locations.