Cross coupling matrix for selector switches in telephone exchange - has three relays controlling gates that operate selector switches

摘要

The cross-coupling matrix, for selector switches of a telephone exchange in a monitoring complex is used for switching through to a central unit. Each measuring selector instrument is coupled via its own switch to the input of a common amplifier with alternating current connection to the central unit. The switches are controlled by the outputs of gates, each of which has three inputs. The three inputs are connected over three relay contacts to a positive voltage. The relays containing these contacts are operated separately by the central unit, to switch the appropriate measuring instrument switch. all the gates' three inputs are connected to the same three relay contacts.