Circuit for connecting and decoupling a two-wire line to the or respectively from the speech and transmission path and the listening and receiving branch of a multiple-wire line

• Main Author: G. PRENOSIL,WOLFGANG
• Format: Patent
• Language: English; German
• Published: 10.01.1985
• Edition: 3
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION

For this purpose, hybrid circuits are provided which exhibit bridge arrangements which contain two resistors of equal size in each bridge branch. The eight resistors of a bridge arrangement are thus of equal size. The signals to be conducted via the hybrid circuits are conducted via the non-inverting and the inverting inputs of amplifiers belonging together in pairs so that they are present either in the same phase or in opposite phase at certain points of the bridge arrangement or lead away from this via amplifiers. Depending on the object and desired direction of flow of the signals, these are picked up at other diagonal points of the bridge arrangement and supplied to the inverting or non-inverting inputs of one or two operational amplifiers. This results either in an unattenuated or, in the ideal case, no signal at the output of the amplifiers. By means of corresponding circuits connected to the amplifier outputs, the signals are present highly attenuated (infinitely attenuated in the ideal case) or unattenuated at the intended interfaces.