GB543388A - Improvements in installations for conversation in both directions between two points - Google Patents

Improvements in installations for conversation in both directions between two points

Info

Publication number
GB543388A
GB543388A GB812640A GB812640A GB543388A GB 543388 A GB543388 A GB 543388A GB 812640 A GB812640 A GB 812640A GB 812640 A GB812640 A GB 812640A GB 543388 A GB543388 A GB 543388A
Authority
GB
United Kingdom
Prior art keywords
directions
instrument
baffle
amplifier
acting
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
GB812640A
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.)
Koninklijke Philips NV
Original Assignee
Philips Gloeilampenfabrieken NV
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 Philips Gloeilampenfabrieken NV filed Critical Philips Gloeilampenfabrieken NV
Priority to GB812640A priority Critical patent/GB543388A/en
Publication of GB543388A publication Critical patent/GB543388A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/001—Two-way communication systems between a limited number of parties

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Headphones And Earphones (AREA)
  • Amplifiers (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)

Abstract

543,388. Direct-call systems. PHILIPS LAMPS, Ltd. (Naamlooze Vennootschap Philip's Gloeilampenfabrieken). May 6, 1940, No. 8126. [A Specification was laid open to inspection under Sect. 91 of the Acts, Nov. 11, 1940.] [Class 40 (iv)] Two stations have combined loudspeakers 10, 15 acting also as microphones, one being provided with a baffle 18 so that due to variation in low frequency response of the instruments when acting as a loudspeaker or microphone and with or without the baffle, a straight line characteristic is obtained for both directions of transmission. Additional instruments 16, 17, with baffles, may be connected in parallel with the instrument 15. Separate amplifiers 13, 14 for the two directions of speech are permanently connected to instrument 15, but instrument 10 is provided with a manual switch 12 whereby it may be connected to the input of amplifier 13 or output of amplifier 14.
GB812640A 1940-05-06 1940-05-06 Improvements in installations for conversation in both directions between two points Expired GB543388A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB812640A GB543388A (en) 1940-05-06 1940-05-06 Improvements in installations for conversation in both directions between two points

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB812640A GB543388A (en) 1940-05-06 1940-05-06 Improvements in installations for conversation in both directions between two points

Publications (1)

Publication Number Publication Date
GB543388A true GB543388A (en) 1942-02-24

Family

ID=9846244

Family Applications (1)

Application Number Title Priority Date Filing Date
GB812640A Expired GB543388A (en) 1940-05-06 1940-05-06 Improvements in installations for conversation in both directions between two points

Country Status (1)

Country Link
GB (1) GB543388A (en)

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