GB941774A - Improvements in or relating to speech frequency signal receivers - Google Patents

Improvements in or relating to speech frequency signal receivers

Info

Publication number
GB941774A
GB941774A GB1140460A GB1140460A GB941774A GB 941774 A GB941774 A GB 941774A GB 1140460 A GB1140460 A GB 1140460A GB 1140460 A GB1140460 A GB 1140460A GB 941774 A GB941774 A GB 941774A
Authority
GB
United Kingdom
Prior art keywords
diodes
diode
input
frequency signal
series
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
GB1140460A
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 GB941774A publication Critical patent/GB941774A/en
Expired legal-status Critical Current

Links

Classifications

    • 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

Abstract

941,774. Relay circuits. TELEFONAKTIEBOLAGET L. M. ERICSSON. March 31, 1960 [April 1, 1959], No. 11404/60. Headings H3P and H4R. A non-linear circuit comprises an amplifier 6 having a pair of diodes 9, 10 connected in series with the output and a further diode 2 connected to the input. The diodes are biased so that diode 2 attenuates low level input signals whilst diodes 9, 10 block output signals corresponding to a level below E 1 (Fig. 4). Input signals above level E 1 result in a rectified current from diodes 9, 10 which tends to overcome the bias on diode 2, reducing its attenuation so that a pronounced increase in output current occurs sufficient to energize relay 12. The circuit is suitable for use in a voice frequency signalling system of the type in which incoming signals are first fed through an amplitude limiter so that the amplitude of the emergent voice frequency signal is diminished in the presence of speech currents. Transformer 8 and capacitor 13 are preferably resonant at the signalling frequency. In Fig. 1 (not shown), the bias source is connected in series with the resistor 3 and diode 2 is connected in parallel with the input circuit.
GB1140460A 1959-04-01 1960-03-31 Improvements in or relating to speech frequency signal receivers Expired GB941774A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE339259 1959-04-01

Publications (1)

Publication Number Publication Date
GB941774A true GB941774A (en) 1963-11-13

Family

ID=20262014

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1140460A Expired GB941774A (en) 1959-04-01 1960-03-31 Improvements in or relating to speech frequency signal receivers

Country Status (2)

Country Link
DE (1) DE1156120B (en)
GB (1) GB941774A (en)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE634615C (en) * 1932-10-18 1936-08-31 Siemens & Halske Akt Ges Signal receiver for telephone systems
DE688680C (en) * 1937-01-31 1940-02-28 Aeg Circuit for limiting large or suppressing small amplitudes in transmission systems
DE693175C (en) * 1937-03-13 1940-07-03 Aeg osser and suppression of small amplitudes in transmission systems
DE691876C (en) * 1937-05-14 1940-06-07 Aeg Circuit for the simultaneous limitation of large and the suppression of small amplitudes

Also Published As

Publication number Publication date
DE1156120B (en) 1963-10-24

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