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GB894988A - Identification of sound and like signals - Google Patents

Identification of sound and like signals

Info

Publication number
GB894988A
GB894988A GB560659A GB560659A GB894988A GB 894988 A GB894988 A GB 894988A GB 560659 A GB560659 A GB 560659A GB 560659 A GB560659 A GB 560659A GB 894988 A GB894988 A GB 894988A
Authority
GB
United Kingdom
Prior art keywords
narrow band
code
cycles
filter
terminal
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
GB560659A
Inventor
Emil Frank Hembrooke
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.)
MUZAK CORP
Original Assignee
MUZAK CORP
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 MUZAK CORP filed Critical MUZAK CORP
Priority to GB560659A priority Critical patent/GB894988A/en
Publication of GB894988A publication Critical patent/GB894988A/en
Expired legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04KSECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K1/00Secret communication

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)

Abstract

894,988. Sound records. MUZAK CORPORATION. Feb. 18, 1959, No. 5606/59. Class 40 (2). [Also in Group XXXIX] In order to identify the origin of a recorded musical or other audio programme, a narrow band within the programme range is modulated in accordance with a characteristic code, e.g. by Morse interruptions, the presence of the code being imperceptible to a listener in normal reproduction. The narrow band may, for example, be 10 cycles in width in the vicinity of 1000 cycles. As shown, the audio signals are switched by means of a coding key 12, which may be cam-controlled, either directly from terminal 11 to terminal 13 or through a filter 14 which rejects the narrow band. In order to detect the identifying code in reproduction, the narrow band is selected by a filter 22 and fed to a transducer 23 which may comprise a recording meter, an oscilloscope or a loud-speaker.
GB560659A 1959-02-18 1959-02-18 Identification of sound and like signals Expired GB894988A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB560659A GB894988A (en) 1959-02-18 1959-02-18 Identification of sound and like signals

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB560659A GB894988A (en) 1959-02-18 1959-02-18 Identification of sound and like signals

Publications (1)

Publication Number Publication Date
GB894988A true GB894988A (en) 1962-04-26

Family

ID=9799247

Family Applications (1)

Application Number Title Priority Date Filing Date
GB560659A Expired GB894988A (en) 1959-02-18 1959-02-18 Identification of sound and like signals

Country Status (1)

Country Link
GB (1) GB894988A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4280020A (en) 1979-01-09 1981-07-21 Essex County Council Radio telephone system with direct digital carrier modulation for data transmission
GB2196167A (en) * 1986-10-01 1988-04-20 Emi Plc Thorn Encoded marking of a recording signal
EP0577126A1 (en) * 1992-07-02 1994-01-05 GRUNDIG E.M.V. Elektro-Mechanische Versuchsanstalt Max Grundig GmbH & Co. KG Method and circuit arrangement for marking voice signals

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4280020A (en) 1979-01-09 1981-07-21 Essex County Council Radio telephone system with direct digital carrier modulation for data transmission
GB2196167A (en) * 1986-10-01 1988-04-20 Emi Plc Thorn Encoded marking of a recording signal
GB2196167B (en) * 1986-10-01 1991-01-02 Emi Plc Thorn Apparatus for marking a recorded signal
EP0577126A1 (en) * 1992-07-02 1994-01-05 GRUNDIG E.M.V. Elektro-Mechanische Versuchsanstalt Max Grundig GmbH & Co. KG Method and circuit arrangement for marking voice signals

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