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GB962146A - Improvements in or relating to communication systems - Google Patents

Improvements in or relating to communication systems

Info

Publication number
GB962146A
GB962146A GB516262A GB516262A GB962146A GB 962146 A GB962146 A GB 962146A GB 516262 A GB516262 A GB 516262A GB 516262 A GB516262 A GB 516262A GB 962146 A GB962146 A GB 962146A
Authority
GB
United Kingdom
Prior art keywords
electromagnetic
modulation
carrier frequency
output
signal
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
GB516262A
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.)
Modern Telephones Great Britain Ltd
Original Assignee
Modern Telephones Great Britain Ltd
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 Modern Telephones Great Britain Ltd filed Critical Modern Telephones Great Britain Ltd
Priority to GB516262A priority Critical patent/GB962146A/en
Publication of GB962146A publication Critical patent/GB962146A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B3/00—Audible signalling systems; Audible personal calling systems
    • G08B3/10—Audible signalling systems; Audible personal calling systems using electric transmission; using electromagnetic transmission
    • G08B3/1008—Personal calling arrangements or devices, i.e. paging systems
    • G08B3/1016—Personal calling arrangements or devices, i.e. paging systems using wireless transmission
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B3/00—Audible signalling systems; Audible personal calling systems
    • G08B3/10—Audible signalling systems; Audible personal calling systems using electric transmission; using electromagnetic transmission
    • G08B3/1008—Personal calling arrangements or devices, i.e. paging systems
    • G08B3/1016—Personal calling arrangements or devices, i.e. paging systems using wireless transmission
    • G08B3/1025—Paging receivers with audible signalling details
    • G08B3/1066—Paging receivers with audible signalling details with other provisions not elsewhere provided for, e.g. turn-off protection

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Radio Relay Systems (AREA)

Abstract

962,146. Ultrasonic signalling apparatus. MODERN TELEPHONES (GREAT BRITAIN) Ltd., and M. MILLETT. Feb. 5, 1963 [Feb. 9, 1962], No. 5162/62. Heading G4F. [Also in Division H4] A communication system comprises means for transmitting a modulated ultrasonic signal, and means for detecting the signal to produce an output in accordance with the modulation, combined with an electromagnetic transmission system. In one embodiment, Fig. 2, both systems employ the same carrier frequency, so that the same carrier frequency oscillator 22, modulator 23, modulation generator 24 and demodulator 29 may be employed for both systems. The output from the modulator is fed to an acoustic transmitter 24, and an electromagnetic transmitter 26 and the transmitted signals are picked up by receivers 32, 27 respectively. After demodulation the combined output is fed to an indicator 36, a discriminator circuit 35 being included so that the indicator 36 is operated only by a specific modulation tone. The switch 34 may be then operated connecting the speaker 31 so that a message may be received. A different carrier frequency and separate modulation and demodulation equipment may be employed for the electromagnetic path, Fig. 3 (not shown), or the electromagnetic signal may be transmitted directly without a carrier.
GB516262A 1962-02-09 1962-02-09 Improvements in or relating to communication systems Expired GB962146A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB516262A GB962146A (en) 1962-02-09 1962-02-09 Improvements in or relating to communication systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB516262A GB962146A (en) 1962-02-09 1962-02-09 Improvements in or relating to communication systems

Publications (1)

Publication Number Publication Date
GB962146A true GB962146A (en) 1964-07-01

Family

ID=9790853

Family Applications (1)

Application Number Title Priority Date Filing Date
GB516262A Expired GB962146A (en) 1962-02-09 1962-02-09 Improvements in or relating to communication systems

Country Status (1)

Country Link
GB (1) GB962146A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3784970A (en) * 1971-02-17 1974-01-08 W Simpkin Emergency warning system with range control
US4523193A (en) * 1983-11-21 1985-06-11 Levinson Samuel H Remote-controlled doorbell signal receiver

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3784970A (en) * 1971-02-17 1974-01-08 W Simpkin Emergency warning system with range control
US4523193A (en) * 1983-11-21 1985-06-11 Levinson Samuel H Remote-controlled doorbell signal receiver

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