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: In a .pi./2 power divider, particularly a .pi./2 hybrid for the radio-frequency antenna of a nuclear magnetic resonance tomography apparatus, a decoupling circuit having unbalanced-to-ground line transformers is provided. Each branch thereof contains an all pass network consisting unbalanced-to-ground line transformers at the output. A broadband .pi./2 hybrid is obtained particularly with a broadband 3 dB/180.degree. hybrid as the decoupling circuit.

Abstract: An improved, high frequency, high or low power, broadband quadrature combiner having a significant reduction in weight, and improved electrical performance such as, decreased insertion loss, improved phase linearity, reduced Intermodulation Distortion (IMD) and improved VSWR, as well as improved simplified tuning opportunities. A reduction in the number of transformers used in the prior art quadrature combiner design facilitates weight reduction and independent tuning of a zero and ninety degree phase network. Specific design improvements to the prior art quadrature combiner include: elimination of the input hybrid, scaling of the phase networks to twice its prior art impedance and optimization of values over the frequency range, and the substitution of an output hybrid utilizing a single hybrid transformer in series with an impedance matching transformer.

Abstract: A signal splitter connects a radio frequency signal source to a pair of output loads, e.g., separate receivers, and has an increased high-end frequency response as compared to similar devices. First and second tubular cores are disposed side by side, each with a pair of toroidal windings therein. An input end of the first winding of the first core is coupled to the signal input and the second end of the second winding to ground, respectively, while output ends of the windings in the second core are connected to the output loads. The other ends of the windings of the two cores are respectively connected to one another to form two single-pair twisted connections. These are passed into through holes of a printed circuit board and are soldered or otherwise electrically connected to a printed conductor on the board. This construction reduces stray inductance significantly and also provides better mechanical mounting than previous devices. The two tubular cores could be fused as a single core with two holes.

Abstract: At a transmission line (La', Lb') connected with telephone station equipment (Tel) via a lowpass filter (TP), via which telephone station signals are transmitted in a first frequency range, there is connected via a line transformer (U3) a data terminal (DG) which is able to receive and to send data signals in a second frequency range above the first frequency range. On its side toward the transmission line (La', Lb'), the lowpass filter (TP) has a capacitive termination (C7) which is rated so that its a-c resistance is in the order of magnitude of or preferably less than the characteristic impedance of the data transmission line in the second frequency range.

Abstract: A simplified balancing impedance (Z.sub.2) included in a transformer fork has a constant capacitor (C.sub.5) connected in series with the termination resistor (R.sub.1). The variable capacitance in the balancing impedance contains a resistor-capacitor network (R.sub.2, C.sub.6 ; R.sub.3 C.sub.7, C.sub.8 -C.sub.11) connected in parallel with the termination resistance. The constant capacitor and the center point capacitor (C.sub.2) on the balancing side of the fork can thus be replaced by one capacitor.

Abstract: Voice-band signals are coupled to and from a telephone subscriber line via a low-pass filter which has a shunt capacitor coupled across the line. In order to simultaneously couple above voice-band signals to and from the line, this capacitor is coupled to the line via windings of a transformer. The above voice-band signals are coupled via at least one series inductor and the transformer to the line, the inductor being series resonant with the filter capacitor, as reflected through the transformer, at the above voice-band signal frequency. Two such series inductors provide for efficient coupling of signals to and from the line at two different frequencies, facilitating simultaneous transmission and reception of above voice-band signals, for example FSK data signals, via the line. Parallel resonant circuits are also provided to prevent degradation of the filter characteristics in the voice-band and to prevent coupling of receive frequency components from the transmit signal to the receive signal line.

Abstract: Voice-band signals are coupled to and from a telephone subscriber line via a low-pass filter which has a shunt capacitor coupled across the line. In order to simultaneously couple above voice-band signals to and from the line, this capacitor is coupled to the line via windings of a transformer. The above voice-band signals are coupled via the transformer to and from the line, for example via series inductors which are series resonant with the filter capacitor, as reflected through the transformer, at above voice-band signal frequencies. A parallel resonant circuit, which has a low impedance in the voice-band, is connected in parallel with a winding of the transformer to prevent degradation of the filter characteristics in the voice-band.

Abstract: One circuit is a low frequency, wide band multi-directional tap that exhibits good match characteristics with low through loss. The circuit has input and output terminals conductively interconnected, a tap output terminal, an inductive winding having n.sub.1 /n.sub.2 series turns and a series resistor coupling from the tap on the inductive winding to the tap output terminal. The other circuit is a low frequency, wide band multi-directional signal splitter that also exhibits good match characteristics with low through loss. The circuit has an input terminal and two output terminals interconnected by three core transformers each having an isolation resistor associated therewith.

Abstract: An n-way power combining or dividing arrangement comprising n-transformers and n-input (combiner) or output (divider) terminals and n-balancing loads which are so arranged that the impedance at each input or output terminal remains substantially constant irrespective of the number of input terminals which are actively driven or, as the case may be, output terminals from which power is actively taken. Each input terminal is connected to one end of a respective one of the balancing loads, the other ends of which are connected together.

Abstract: A multicoupler for coupling a single energy source to a plurality of utilization devices including an impedance transformer connected to the source and driving at least one active device such as a pair of series connected emitter followers. A plurality of isolation networks are each connected to the output of the active device and each of said isolation networks provides an output for at least one utilization device.

Abstract: In branching equipment for CATV systems, including a distributing transformer consisting of a tapped winding, ends of which are connected to a pair of output terminals whereby a television signal applied to the tap is distributed to the output terminals with a current level ratio determined by the ratio of the number of turns in the winding portion on one side of the tap to that in the winding portion on the other side of the tap, an electric power absorbing resistor is connected between the tap and one of the output terminals so as to reduce the interaction of undesired signals between the output terminals.

Abstract: The present invention relates to a divider network for dividing an HF signal into n output signals of the same power and phase at the same impedance as the input, where n is a positive integer greater than 1. Each of the n signals is fed to an output port. Each of the output ports has associated therewith a transformer. Each of the ports is connected to ground via at least one winding of the transformer. Each of the ports is connected to a common point by a winding of the transformer so that each transformer is connected in parallel with respect to the common point. The HF signal is fed to the divider via an input port. The input port is connected to the common point so that the path length between the input port and each of the output ports is substantially equal.