GB475952A - Improvements in and relating to telephone systems - Google Patents
Improvements in and relating to telephone systemsInfo
- Publication number
- GB475952A GB475952A GB5215/36A GB521536A GB475952A GB 475952 A GB475952 A GB 475952A GB 5215/36 A GB5215/36 A GB 5215/36A GB 521536 A GB521536 A GB 521536A GB 475952 A GB475952 A GB 475952A
- Authority
- GB
- United Kingdom
- Prior art keywords
- automatic
- switchboard
- local battery
- key
- exchange
- 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
- H04M—TELEPHONIC COMMUNICATION
- H04M9/00—Arrangements for interconnection not involving centralised switching
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Interface Circuits In Exchanges (AREA)
Abstract
475,952. Exchange systems. AUTOPHON AKT.-GES. Feb. 20, 1936, No. 5215. Void. Convention date, Feb. 20, 1935. [Class 40 (iv)] A local battery switchboard, such as a field switchboard, is associated with certain lines at the main frame of an automatic or other exchange by means of an auxiliary device comprising two position keys OB, Wand D, V, push-button keys M, drop indicators FKl and indicators SZ as shown in Fig. 3, so that they may communicate via the automatic apparatus if it is still working or via the local battery switchboard and so that lines connected to the local battery switchboard can be extended via the automatic apparatus. The auxiliary device is connected in by means of plugs of the type in common use for associating test apparatus. In a simplified arrangement, Fig. 2 (not shown), certain lines are automatically connected to the emergency switchboard when the exchange is destroyed. The description is imperfect. Circuit arrangements. (1) Calls originated by automatic subscriber. With the keys in the normal position as shown, the looping of the line Zt energizes A which energizes C. As a result, the indicator Sz is operated and an impulse is given over the wires zKS to operate one of the drop indicators in the local battery switchboard (not shown). The attendant may then (a) extend the call over the local battery switchboard or (b) operate the key D to give the subscriber control of the automatic switches in the ordinary way in which case the relapse of A, C puts the indicator Sz into the line to give supervisory signals to the operator of the auxiliary device who can also listen-in with the aid of the key M, or (c) operate the key to associate the dial AAG with the automatic exchange apparatus, establish a connection over such apparatus and hold it by throwing key V while the calling subscriber is recalled if necessary. (2) Calls originated by local battery sets connected to automatic exchange lines. In this case key OB is thrown and the line appears in the local battery switchboard in the ordinary way. The call can be extended over the automatic switches as described under 1 (c) above. (3) Calls originated by lines on the local battery switchboard are established over the automatic apparatus as described under (2) above. (4) Calls from the automatic apparatus operate the drop indicator FKL and can be extended by the key V to the line ZT, a further contact of V operating the ring-trip relay.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE475952X | 1935-02-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB475952A true GB475952A (en) | 1937-11-29 |
Family
ID=6541928
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB5215/36A Expired GB475952A (en) | 1935-02-20 | 1936-02-20 | Improvements in and relating to telephone systems |
Country Status (2)
Country | Link |
---|---|
FR (1) | FR802148A (en) |
GB (1) | GB475952A (en) |
-
1936
- 1936-02-20 FR FR802148D patent/FR802148A/en not_active Expired
- 1936-02-20 GB GB5215/36A patent/GB475952A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
FR802148A (en) | 1936-08-28 |
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