CIRCUIT ARRANGEMENT OF A TESTER FOR MONITORING OPERATION OF A SWITCHING STAGE SELECTOR IN CROSSBAR SWITCH TYPE EXCHANGES

摘要

Tester system controlling operations of the crossbar telephone exchange access selector, consisting of tested connections switches and a matrix indicating conditions of the connection bridges forming the contact field of a selector being tested; is characterised in that that it has two seven pole switches (P1, P2) with brushes connected to negative power terminal, while each of the six stationary contacts of those switches are connected to the sequential six contacts of two bars (ha, hb) of each of the ten selector bridges (V1-V10), whose voltage coils are connected to power via oscillating switches (v1 - v 10), while the selector bridges (V1- V10) have unstable phone keys (H1 - H10) connected to voltage coils of ten pole twelve-contact selector bars (h1 - h10), while the respective bar contacts (h1 - h10) in sequential bridges (V1 - V10) of the selector are closed and are connected through the short circuiting switches (1 - 12) of the relays (SN1 - SN10) with cathodes of electroluminescent diodes (A - M) of the indicator matrix, whose anodes are connected, via ballast resistors (R1 - R12), with positive power terminal, with each of the relays (SN1 - SN10) connected to the power source via respective oscillating switch (sn1 - sn10).IMAGE