GB283135A - - Google Patents

Info

Publication number
GB283135A
GB283135A GB35140/27A GB3514027A GB283135A GB 283135 A GB283135 A GB 283135A GB 35140/27 A GB35140/27 A GB 35140/27A GB 3514027 A GB3514027 A GB 3514027A GB 283135 A GB283135 A GB 283135A
Authority
GB
United Kingdom
Prior art keywords
currents
signal
frequencies
relay
grid
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
Application number
GB35140/27A
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.)
Telefonaktiebolaget LM Ericsson AB
Original Assignee
Telefonaktiebolaget LM Ericsson AB
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 Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Publication of GB283135A publication Critical patent/GB283135A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/42—Circuits for by-passing of ringing signals
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
    • H04Q1/446—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency
    • H04Q1/4465—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency the same frequency being used for all signalling information, e.g. A.C. nr.9 system

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Selective Calling Equipment (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

283,135. Telefonaktiebolaget L. M. Ericsson, (Assignees of Laurent, T.). Jan. 4, 1927, [Convention date]. Manual exchange systems. - In systems in which currents of a broad range of frequencies such as voice frequencies and other signals of a narrow range within the broad range such as calling and clearing signals are transmitted over the same long-distance line, the receiving arrangements comprise a blocking device responsive to frequencies other than the signal frequencies to prevent incorrect operation of the signalling means by speech currents. In one arrangement, Fig. 1, the anode circuit of an amplifier 10 associated with the incoming end 11, 12 of the line contains filter circuits 15, 16, the former being non-permeable to signal currents so that these pass through transformer 6 to operate a relay 2, whilst the circuit 16 passes only signal currents so that all other frequencies pass to transformer 7 and operate relay 3. Signal currents thus operate signalling device 1 whilst other voice frequencies hold open the signalling circuit. The construction of filters 15, 16 is such that if voice currents of signal frequency arrive at the commencement of operations, relay 3 will act more quickly than relay 2 to prevent its falling back in response to momentary speech-currents of signal frequency. In another arrangement, Fig. 2, the signal 1 is controlled by a single relay 19 in the anode circuit of a valve 20 to the grid of which are connected neon tubes 25, 26. Signal currents passing through transformer 6 render tube 25 conducting and increase the positive potential on the grid, thus operating relay 19. On the other hand, voice currents render tube 26 conducting and make the grid more negative. In a modification, the secondary of transformer 6 is directly connected to the grid of valve 20, but a neon tube is connected directly between grid and filament, The invention is stated to be applicable also to wireless telephone systems, to systems in which a carrier current of voice frequency is employed and to telegraph systems.
GB35140/27A 1927-01-04 1927-12-28 Expired GB283135A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE283135T 1927-01-04

Publications (1)

Publication Number Publication Date
GB283135A true GB283135A (en) 1928-03-29

Family

ID=31944976

Family Applications (1)

Application Number Title Priority Date Filing Date
GB35140/27A Expired GB283135A (en) 1927-01-04 1927-12-28

Country Status (5)

Country Link
US (1) US1958166A (en)
BE (1) BE347704A (en)
DE (1) DE609601C (en)
GB (1) GB283135A (en)
NL (2) NL39470B (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE742806C (en) * 1938-09-01 1943-12-11 Siemens Ag Transmission system with level regulation by a control frequency, in which the response of the control frequency receiver to the useful frequencies is prevented
DE745228C (en) * 1939-07-28 1944-03-01 Siemens Ag Electrical signal receiver
BE454346A (en) * 1943-03-08
FR996042A (en) * 1945-04-14 1951-12-12 Development of pulse signalers
BE478607A (en) * 1945-12-20
FR928242A (en) * 1946-05-18 1947-11-21 Materiel Telephonique Electrical signaling systems
US2511617A (en) * 1946-10-11 1950-06-13 Bell Telephone Laboroatories I Power line carrier frequency telephone system
FR961481A (en) * 1947-02-21 1950-05-12
DE841765C (en) * 1948-10-02 1952-06-19 Normalzeit G M B H Circuit arrangement for telephone systems with audio frequency selection
BE501904A (en) * 1950-03-17
DE954519C (en) * 1951-12-13 1956-12-20 Standard Elek K Ag Circuit arrangement for receiving call and dialing signals
US2935731A (en) * 1957-02-26 1960-05-03 Richter Robert Selective signalling system

Also Published As

Publication number Publication date
NL39470B (en)
US1958166A (en) 1934-05-08
DE609601C (en) 1935-02-23
BE347704A (en)
NL26143C (en)

Similar Documents

Publication Publication Date Title
GB283135A (en)
US2059562A (en) Gas-filled tube telegraph
US2951911A (en) Arrangement for automatic signalling system intended for transmitting voice-frequency calling signals
US2018464A (en) Voice operated transmission circuit
US2273945A (en) Two-way speech transmission
GB398546A (en) Improvements in circuits for modifying the wave-form of electric signals such as telegraph signals
US2306067A (en) Telephone system
GB397551A (en) Improvements in electrical impedance networks and amplifiers
US2336362A (en) Telegraph system
GB501915A (en) Telephone exchange systems
US2071476A (en) Telegraph system
US1829837A (en) Signaling system
US1377405A (en) Audion-circuit
US1955875A (en) Signaling system
US2283760A (en) Duplex signaling system
US1474430A (en) Telephone bepeatee
GB323804A (en) Improvements in impulse controlling arrangements for use in electrical signalling systems
US2370403A (en) Telephone system
US2047304A (en) Signaling system
GB301353A (en) Improvements in signalling arrangements, particularly for use in telephone systems
GB613741A (en) Improvements in or relating to radio and other transmitting and receiving systems
US1353031A (en) Vacuum-bulb for signaling apparatus
GB375346A (en) Improvements in audio frequency signalling systems
GB301317A (en) Improvements in simultaneous telegraphy and telephony systems
US1747863A (en) Electrical signaling