公开(公告)号：FR2352448A1

公开(公告)日：1977-12-16

申请号：FR7616128

申请日：1976-05-21

Applicant: IBM FRANCE

Inventor： FERRY MICHEL ,  REYNES DANIEL

IPC: H01H47/32 ,  H01F7/18 ,  H01L27/07 ,  H03K17/0814 ,  H03K17/10 ,  H03K17/64 ,  H03K17/08

公开(公告)号：FR2462006A1

公开(公告)日：1981-02-06

申请号：FR7919131

申请日：1979-07-20

Applicant: IBM FRANCE

Inventor： MORLEC EMILE ,  REYNES DANIEL ,  SUZZONI JEAN-PIERRE

IPC: H01F19/00 ,  H03H11/48 ,  H04M19/00 ,  H04Q3/42 ,  H04Q3/52 ,  H01F17/00 ,  H04B3/18 ,  H04M1/76

Abstract: A switching network includes electronic crosspoint switches for providing electronic connection or disconnection between two voice stations. Each station is connected to the network through a line transformer. When two stations are connected to each other, the voice path in the network includes the secondary winding of the 1st station transformer, a series of crosspoint switches, a middle junctor, a series of crosspoint switches, and the secondary winding of the 2nd station transformer. Each middle junctor includes a negative resistance circuit which introduces a negative resistance in series with the voice path, thus compensating for the series losses in the network, and two negative inductance circuits connected on both sides of the junctor in parallel with the voice path, to compensate for the parallel losses, especially those introduced by the line transformers.

公开(公告)号：FR2386210A1

公开(公告)日：1978-10-27

申请号：FR7710338

申请日：1977-03-31

Applicant: IBM FRANCE

Inventor： GRANGE JEAN-CLAUDE ,  HERNANDEZ PHILIPPE ,  REYNES DANIEL ,  SUZZONI JEAN-PIERRE ,  TU NGHIEM HO

IPC: H04Q3/72 ,  H04M3/02 ,  H04M19/02 ,  H04M3/30

Abstract: A circuit associated with a telephone line to detect line status includes a first detector sensitive to the line current phase, a second detector sensitive to the ringing voltage phase, and two pulse generators of the same frequency as the ringing voltage, appearing at the positive and negative zero-crossings of the ringing voltage, respectively. When only the ringing current is applied to the line, only the signals from both detectors and one generator are simultaneously present (once per period). When the called subscriber lifts his handset, the signals from both detectors and the other generator are also simultaneously present once per period. These pulse coincidences are detected and processed by an appropriate logic.