Telephone system for operator connected calls - has access to central control unit via reduced size keyboard

摘要

The special telephone switching system for operator-connected calls is designed to reduce the size of keyboards by a reduction in the number of necessary operating keys. Each subscriber is connected to the desired repeater by calling an operator position. The operator operates an assignment key to initiate a control programme via a coupling unit and central control unit. Group selection is then made via a dialler. The output of the selector register is translated to operate a search unit via contacts in an allocator. The search unit then selects the first free outlet in the group. A priority circuit in the coupler ensures that only one selection is made at a time between respective subscribers and operators.