| | Circuit for the parallel coupling of audio frequency central-control transmitting stations in a wave band filter ... |
 | | A circuit according to claim 1, wherein a generator-side series resonant circuit, comprising a third inductance coil in series with a third capacitor, is connected in series between said generator-side parallel resonant circuit and the audio frequency generator, said generator-side series resonant circuit being tuned to the output frequency of the audio frequency generator. |
 | | A circuit according to claim 5, wherein the ratio of the impedance of said generator-side series resonant circuit to the impedance of said generator-side parallel resonant circuit at the output frequency of the audio frequency generator is in the range 0.3 to 1.0. |
 | | In another known parallel coupling, two series resonant circuits are used for similar reasons, one of said circuits being on the system side and one on the audio generator side, and wherein the coils of said circuits are connected in a transformer relationship, preferably coupled hypercritically, but electrically separated. |
| www.freepatentsonline.com /4078216.html (1835 words) |