GB574312A - Improvements in or relating to automatic switches for use in telephone or like systems - Google Patents
Improvements in or relating to automatic switches for use in telephone or like systemsInfo
- Publication number
- GB574312A GB574312A GB1825/44A GB182544A GB574312A GB 574312 A GB574312 A GB 574312A GB 1825/44 A GB1825/44 A GB 1825/44A GB 182544 A GB182544 A GB 182544A GB 574312 A GB574312 A GB 574312A
- Authority
- GB
- United Kingdom
- Prior art keywords
- relay
- selector
- ground
- toll
- line
- Prior art date
- 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
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q3/00—Selecting arrangements
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Interface Circuits In Exchanges (AREA)
- Monitoring And Testing Of Exchanges (AREA)
Abstract
574,312. Automatic exchange systems. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd., TAYLOR, R., and BAKER, G. T. Feb. 1, 1944, No. 1825. [Class 40 (iv)] In a subscriber's line switch of the homing type, on an outgoing call potential is applied to the guarding conductor leading to the final selector multiple through the cut-off relay, which is of low resistance, and a wiper of the switch in off-normal position, so that the relay may be released by the application of the same potential from a final selector extending a toll call. The operation of line relay L starts hunting in the usual manner, and cut-off relay K pulls up in series with the magnet DM when an idle outlet is found. After the relapse of relay L, the holding ground fed back from the seized selector is extended through relay K and over wiper D2 to the incoming test wire. If now direct ground is applied to this wire from a toll final selector, relay K is shortcircuited, the existing connection is opened and the switch restores to normal, whereupon circuits are made for both relays K, L, but K operates first and disconnects L. If the subscriber is the called party in an existing connection, the breakdown ground will maintain relay K and force down the switching relay in the final selector. Relay K may be shunted by a condenser to pass the toll tone that is usually provided on toll calls. The common battery (or ground) lead 10 to the line relays may include a key LDK which serves to disable non-priority subscribers as regards outgoing calls during overload conditions. On long lines the release lag of relay L may be reduced to provide greater winding space and therefore it is arranged that holding ground is fed back from the first selector immediately upon operation of the line relay. A selector is described that is otherwise similar to that disclosed in Specification 447,767.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1825/44A GB574312A (en) | 1944-02-01 | 1944-02-01 | Improvements in or relating to automatic switches for use in telephone or like systems |
US567551A US2424519A (en) | 1944-02-01 | 1944-12-11 | Nonnumerical rotary homing type switch |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1825/44A GB574312A (en) | 1944-02-01 | 1944-02-01 | Improvements in or relating to automatic switches for use in telephone or like systems |
Publications (1)
Publication Number | Publication Date |
---|---|
GB574312A true GB574312A (en) | 1945-12-31 |
Family
ID=9728658
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1825/44A Expired GB574312A (en) | 1944-02-01 | 1944-02-01 | Improvements in or relating to automatic switches for use in telephone or like systems |
Country Status (2)
Country | Link |
---|---|
US (1) | US2424519A (en) |
GB (1) | GB574312A (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL165657B (en) * | 1950-11-29 | Francken Frank | SPORT VEHICLE ON WHICH A USER CAN SIT AND DRIVE WITH FEET. |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1718976A (en) * | 1929-07-02 | ostline | ||
US1669031A (en) * | 1925-05-09 | 1928-05-08 | Automatic Electric Inc | Rotary line switch |
GB261880A (en) * | 1925-09-28 | 1926-12-02 | Automatic Telephone Mfg Co Ltd | Improvements in or relating to telephone systems |
-
1944
- 1944-02-01 GB GB1825/44A patent/GB574312A/en not_active Expired
- 1944-12-11 US US567551A patent/US2424519A/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
US2424519A (en) | 1947-07-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB567864A (en) | Improvements in or relating to telecommunication exchange systems | |
US3133995A (en) | Call awaiting signal telephone circuits | |
GB574312A (en) | Improvements in or relating to automatic switches for use in telephone or like systems | |
US2292371A (en) | Repeater circuit | |
US2892038A (en) | Line adapter circuit for special telephone service | |
GB522457A (en) | Improvements in or relating to systems of simultaneous telephony on a number of lines | |
US2060585A (en) | Telephone signal circuit | |
GB616834A (en) | Improvements in or relating to automatic switches for use in telephone systems | |
US3320367A (en) | Telephone line circuit | |
GB583373A (en) | Improvements in automatic switches for use in telephone or like systems | |
GB1099697A (en) | Improvements in or relating to private branch exchange telephone switching systems | |
US3041410A (en) | Delay busy circuit | |
US2260722A (en) | Telephone system | |
US2338997A (en) | Communication system | |
US2105898A (en) | Telephone exchange system | |
US2855463A (en) | Telephone system involving the dialing of extension stations at a cordless p. b. x | |
US2322864A (en) | Trouble cutoff system | |
US1675310A (en) | Telephone system | |
US3544730A (en) | Trunk signalling and supervision control | |
US1218806A (en) | Telephone trunking system. | |
GB542011A (en) | Improvements in or relating to telephone systems | |
US2546067A (en) | Two-way telephone trunk circuit | |
US2702832A (en) | Telephone system | |
US1688689A (en) | Automatic telephone system | |
US1738059A (en) | Telephone system |