Abstract: Ingress noise from subscriber equipment is mitigated or prevented from reaching a cable television (CATV) network. All upstream signals including ingress noise are initially transmitted to the CATV network whenever their instantaneous power exceeds a threshold which typically distinguishes ingress noise from a valid upstream signal. Whenever the instantaneous power is below the threshold, ingress noise is blocked from reaching the CATV network. A gas tube surge protection device is included to resist component destruction and malfunction arising from lightning strikes and other high voltage, high current surges.

Abstract: A Radio Frequency (RF)-band tuner stage is combined with a quadrature downconverter stage in a single shielded enclosure as an RF-to-baseband pulse amplitude modulated tuner suitable for receiving RF-band signals from an LNB or the like and converting the signals directly to signals in a desired digital format. The bandwidths within the two stages are optimized for digital PAM demodulation, such as PSK or QAM, and certain functions are shared, such as automatic gain control and carrier tracking information. Electronically switchable attenuators and voltage-variable gain controlled amplifiers, in connection with a low-phase-noise local oscillator employing a microstrip resonator, provide for over 70 dB of dynamic range. The IF frequency and bandwidth are selected so that voltage-variable tunable bandpass filters of conventional design may be used to obtain over 40 dB of radio frequency image rejection necessary for reception of PAM signals.

Abstract: L-band tuner stage is combined with a quadrature downconverter stage in a single shielded enclosure as an L-band-to-baseband PSK tuner suitable for receiving L-band signals from an LNB and converting the signals directly to signals in a desired digital format. The bandwidths within the two stages are optimized for digital PSK demodulation, and certain functions are shared, such as automatic gain control and carrier tracking information. Electronically switchable attenuators and voltage-variable gain controlled amplifiers, in connection with a low-phase-noise local oscillator employing a microstrip resonator, provide for over 70 dB of dynamic range. The IF frequency and bandwidth are selected so that voltage-variable tunable bandpass filters of conventional design may be used to obtain over 40 dB of radio frequency (RF) image rejection necessary for reception of PSK signals.