Abstract: A system and method for collecting on-street parking revenue. The method utilizes a device which establishes a link with a server. Once the device is validated and the location of the vehicle is established, a message is transmitted to the device with the parking rates for that location. The time that the vehicle is parked at the location is tracked. The parking charges are collected electronically by charging the user's account based upon the parking rates and the time that the vehicle was parked at that location.

Abstract: The present invention is a method and apparatus for simply and inexpensively enhancing an electronic audio signal in such a way that the quality of audible sound produced from the audio signal more closely approaches that of the original sound heard live in an acoustically designed environment. The present invention restores the perception of harmonics that are normally missing in an electronic audio signal. The apparatus includes a circuit that causes an input audio signal to be distorted such that an enhanced audio signal is produced that exhibits an improved harmonic quality compared to that of the original input audio signal. This distortion is a non-linear amplification of enhancing harmonics or frequencies in the input audio signal. That is, a band of desirable harmonics or frequencies in the input audio signal are non-uniformly amplified across the band. This band of frequencies from the input audio signal can be a band of high frequencies and/or a band of low frequencies.

Abstract: An electro-acoustic speaker having no permanent magnet. An audio input signal is applied to a pair of parallel coils, each being in series with a diode. The diodes are oppositely acting, so that the coils conduct during alternate half cycles of the input signal. As a result, the coils alternately generate magnetic flux for cooperative establishment of an unidirectional magnetic field. The input signal is also applied to a third coil for generation of a full wave current therethrough. This full wave current produces magnetic flux which establishes an alternating magnetic field. Interactions between the current-carrying coils and their respective magnetic fields produce acceleration forces for a speaker cone.