Abstract: An integrated communications system. A substrate having a receiver disposed on the substrate for converting a received signal to an IF signal, a digital IF demodulator disposed on the substrate and coupled to the receiver for converting the IF signal to a demodulated baseband signal, and a transmitter disposed on the substrate operating in cooperation with the receiver to establish a two way communications path.

Abstract: An integrated communications system. A substrate having a receiver disposed on the substrate for converting a received signal to an IF signal, a digital IF demodulator disposed on the substrate and coupled to the receiver for converting the IF signal to a demodulated baseband signal, and a transmitter disposed on the substrate operating in cooperation with the receiver to establish a two way communications path.

Abstract: An amplifier that accurately amplifies signals over a wide bandwidth, including DC, has a voltage-to-current converter, a feed-forward resistive element, a buffer, an input resistive element, a feedback resistive element, and an operational amplifier. A first end of the feed-forward resistive element is coupled to an output of the voltage-to-current converter and to an input of the buffer. A first end of the input resistive element is coupled to an input to the voltage-to-current converter. A first end of the feedback resistive element is coupled to an output of the buffer. An inverting input of the operational amplifier is coupled to a second end of the input resistive element and to a second end of the feedback resistive element. A noninverting input of the operational amplifier is coupled to ground, and an output of the operational amplifier is coupled to a second end of the feed-forward resistive element.

Abstract: An integrated communications system. A substrate having a receiver disposed on the substrate for converting a received signal to an IF signal, a digital IF demodulator disposed on the substrate and coupled to the receiver for converting the IF signal to a demodulated baseband signal, and a transmitter disposed on the substrate operating in cooperation with the receiver to establish a two way communications path.

Abstract: Apparatus for generating two output signals with a selective predetermined constant phase difference therebetween from an input reference signal having a predetermined frequency and phase includes, in one embodiment, a first and a second Programmable Delay, and a first and a second Synthesizer. The input reference signal is provided as separate inputs to the first and second Programmable Delays which generate first and second output signals, respectively, with selective predetermined delay differences therebetween for transmission to the respective first and second Synthesizers. Each of first and second Synthesizers are phase locked loops with a Programmable Divider and an optional Prescaler added to the loop to divide a high frequency output signal generated by a Voltage Controlled Oscillator (VCO) to a frequency of the output signal from the associated Programmable Delay in order to correct for any phase difference between the output signal of the VCO and the input signal from the Programmable Delay.

Abstract: A double conversion frequency converter includes first and second mixing stages. The first mixing stage includes a first programable Local Oscillator (LO) synthesizer and a first mixer, and the second mixing stage includes a second programable LO synthesizer and a second mixer. The first and second LO synthesizers have a wide band tuning range for receiving a separate predetermined reference signal and generating therefrom first and second LO output signals, respectively, which each are changeable by predetermined large frequency steps. The first mixer mixes an input signal to the frequency converter with the first LO output signal for generating a first predetermined mixer output signal. The second mixer mixes a predetermined sideband generated in the first predetermined mixer output signal with the second LO output signal for generating a second predetermined mixer output signal which is use for the output signal for the frequency converter.

Abstract: An automatic frequency control tracks a television signal before and after a period of interruption. The automatic frequency control comprises a voltage controlled feedback loop including a voltage controlled local oscillator and a mixer for mixing the output of the oscillator with the TV signal. The output of the mixer is filtered to remove unwanted components of the mixed signal and to equalize sidebands of the television signal. The output of the filter is supplied to a detector which is tuned to a component of the television signal, and produces a voltage corresponding to the frequency of the component. The output of the detector is supplied to the voltage control input of the local oscillator to track the television signal component. Circuitry automatically senses the absence of the TV signal component from the mixer, and automatically applies a reference voltage to the voltage control input of the oscillator when the TV signal component is absent.

Abstract: An apparatus and method are provided for receiving and reproducing stereo television sound. A transmitted television signal is received that contains a first component comprising the sum of first and second stereophonically related audio signals and a second component comprising the difference between the first and second stereophonically related audio signals. The first and second components are converted to produce a first sound carrier centered at a first intermediate frequency and a second sound carrier centered at a second intermediate frequency. The first component is detected from the first sound carrier at the first intermediate frequency. The second component is detected from the second sound carrier at the second intermediate frequency. The detected first and second components are combined to produce a left channel audio output and a right channel audio output.