Abstract: A signal processor is provided for encoding telephone dialing signals received from a telephone system at a transmitting station and transmitted using a digital transmission system to a receiving station for decoding and application to a telephone system at the receiving station. The system includes circuitry connected to the telephone system at the transmitting station for detecting and receiving telephone dialing signals generated by the telephone system at the transmitting station. Circuitry is provided for storing the detected telephone dialing signals for a predetermined time period at the transmitting station. The system further includes circuitry interconnected between the circuitry for storing and the digital transmission system for selectively clocking this circuitry to generate digital representations of the telephone dialing signals for transmission to the receiving station.

Abstract: A speech signal synthesizer features a time and frequency scaler for improved accuracy of signal synthesis. A digital signal representative of a first analog signal, such as a voice signal, having varying parameters, such as frequenty or amplitude, is converted by a synthesizer into an analog output signal which varies in substantially the same manner as the first signal. The synthesizer receives a transmitted digital signal representing the first analog signal and synthesizes the varying parameters thereof to provide the analog output signal. First, the digital input signal is applied to a serial-to-parallel converter and subsequently input to a modulated frequency generator controlled by the operation of a modulation controller. Digital data processed through the modulated frequency generator is time and frequency scaled, and it is this time and frequency scaling that provides improved accuracy in recreating the proper amplitude relationship of the first analog signal.