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GB929851A - Improvements relating to hailing equipment - Google Patents

Improvements relating to hailing equipment

Info

Publication number
GB929851A
GB929851A GB1708061A GB1708061A GB929851A GB 929851 A GB929851 A GB 929851A GB 1708061 A GB1708061 A GB 1708061A GB 1708061 A GB1708061 A GB 1708061A GB 929851 A GB929851 A GB 929851A
Authority
GB
United Kingdom
Prior art keywords
switch
amplifier
loud
microphone
speaker
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
GB1708061A
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.)
GUY RUPERT FOUNTAIN
Original Assignee
GUY RUPERT FOUNTAIN
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 GUY RUPERT FOUNTAIN filed Critical GUY RUPERT FOUNTAIN
Publication of GB929851A publication Critical patent/GB929851A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R27/00—Public address systems
    • H04R27/04—Electric megaphones

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Lighting Device Outwards From Vehicle And Optical Signal (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Headphones And Earphones (AREA)

Abstract

929,851. Public address equipment. G. R. FOUNTAIN. March 14, 1962 [May 10, 1961 (2)], Nos. 17080/61 and 17081/61. Class 40 (4). A portable "hailer," mainly for nautical use, comprising a loud-speaker 3, an amplifier 4 and microphone 6 mounted within a casing 1 with a flared horn 2, a battery being enclosed in a hollow handle 5, is provided with a switch 7 which allows the connections of the loudspeaker and microphone to the amplifier to be reversed, so that the user may readily pick up replies to his instructions. An additional earphone 9 may be provided to fit in the user's ear. In a third position of the switch 7 a feed-back connection causes the amplifier to oscillate under the control of a tuned circuit 31, 32 to generate a hooting note in the loud-speaker. A volume control resistance 40 is adjustable by a knob 8. The switch 7 is shown in Fig. 2 as a 3-position switch with 4 banks S1 . . . S4. Specification 842,265 is referred to.
GB1708061A 1965-05-07 1961-05-10 Improvements relating to hailing equipment Expired GB929851A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1939765A GB1105625A (en) 1965-05-07 1965-05-07 Improvements relating to hailing equipment

Publications (1)

Publication Number Publication Date
GB929851A true GB929851A (en) 1963-06-26

Family

ID=10128678

Family Applications (2)

Application Number Title Priority Date Filing Date
GB1708061A Expired GB929851A (en) 1965-05-07 1961-05-10 Improvements relating to hailing equipment
GB1939765A Expired GB1105625A (en) 1965-05-07 1965-05-07 Improvements relating to hailing equipment

Family Applications After (1)

Application Number Title Priority Date Filing Date
GB1939765A Expired GB1105625A (en) 1965-05-07 1965-05-07 Improvements relating to hailing equipment

Country Status (1)

Country Link
GB (2) GB929851A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3412207A (en) * 1965-08-30 1968-11-19 Fedtro Inc Loudspeaker device
DE3536701A1 (en) * 1985-10-15 1987-04-16 Hoermann Gmbh Device for monitoring the function of a sirene

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWM246767U (en) * 2003-10-09 2004-10-11 Sekaku Electron Industry Co Lt Megaphone with lighting device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3412207A (en) * 1965-08-30 1968-11-19 Fedtro Inc Loudspeaker device
DE3536701A1 (en) * 1985-10-15 1987-04-16 Hoermann Gmbh Device for monitoring the function of a sirene

Also Published As

Publication number Publication date
GB1105625A (en) 1968-03-06

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