Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB6902/44A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Standard Telephone and Cables PLCfiledCriticalStandard Telephone and Cables PLC
Publication of GB579010ApublicationCriticalpatent/GB579010A/en
H04Q1/00—Details of selecting apparatus or arrangements
H04Q1/18—Electrical details
Landscapes
Engineering & Computer Science
(AREA)
Computer Networks & Wireless Communication
(AREA)
Interface Circuits In Exchanges
(AREA)
Abstract
579,010. Automatic exchange systems. STANDARD TELEPHONES & CABLES, Ltd. April 14, 1944, No. 6902. Convention date, May 6, 1943. [Class 40 (iv)] In a multi-potential marking system, the selector is controlled by a relay QR connected between the wipers of the register and the selector. The relay is preferably saturated by the current resulting from the minimum potential difference (other than zero) between the wipers and may be associated with a rectifier which ensures that current always flows through QR in the same direction. QR may control the selector indirectly by way of a relay QRA, Fig. 2, which is shunted out while QR is operated but operates momentarily when QR falls. In a modification, Figs. 4 and 5 (not shown), the register and selector wipers are connected respectively to the windings of a differential relay.