Abstract: Diagnostic monitoring apparatus for connection in-line with a cable connecting a first device to a second device and carrying binary information between the first device and the second device over a wire contained in the cable. There is a series connector inserting a connecting wire in series with the wire in the cable. Signal sampling and triggering logic is connected to the connecting wire for sensing any binary signals on the connecting wire and for producing a trigger output when a binary signal is sensed. There is also an illuminatable visible indicator in the form of an LED and a monostable device having the trigger output connected to an input thereof and an output connected to the indicator for producing a signal at the output of sufficient duration to illuminate the indicator for a visibly detectable period of time. The high speed signal sampling and triggering logic is high impedance and connected in parallel to the connecting wire whereby the signal in the wire in the cable is not loaded down.

Abstract: A low frequency multi-port signal coupler employing hybrid transformer coupling circuitry for intercoupling from a main communication line to output taps. In one embodiment, the coupler has two tap ports interconnected by two core transformers, each having a termination resistor associated therewith. In another embodiment of the invention, there are four tap ports interconnected by three core transformers and a shunted inductor, and having three termination resistors and a split-matching isolation resistor associated with the output taps. An impedance matching resistance is provided at the input and output of the two port embodiment.

Abstract: A low frequency multi-port signal coupler employing hybrid transformer coupling circuitry for intercoupling from a main communication line to output taps. In one embodiment, the coupler has two tap ports interconnected by two core transformers, each having a termination resistor associated therewith. In another embodiment of the invention, there are four tap ports interconnected by a single core transformer having a split-matching isolation resistor associated with each output tap, and a pair of termination resistors at the input and output of the primary winding. An impedance matching inductance is provided at the input in both embodiments.

Abstract: A processor providing high-quality audio signals from television sound channels by signal recovery using induced intermodulation between the picture carrier and the sound subcarrier signal. The resulting intermodulation products are filtered and the FM audio subcarrier is recovered and converted to the FM radio band. Subsequently the detected audio signal is enhanced by stereo synthesis and noise reduction systems, producing a high-quality reproduction of television audio signals with a minimum of distortion and noise, suitable for a full-range stereo system. The recovery of the audio subcarrier by inducing intermodulation between the signal carriers avoids the frequency shifts or phase noise induced by satellite and/or CATV translator circuits, in particular, the phase jitter of translating phase-lock loop (PLL) circuits. The converter is also applicable for use with VCR and other equipment to provide high-quality sound recovery.