GB646589A - Improvements in or relating to amplifying devices for use with telephone apparatus - Google Patents

Improvements in or relating to amplifying devices for use with telephone apparatus

Info

Publication number
GB646589A
GB646589A GB207648A GB207648A GB646589A GB 646589 A GB646589 A GB 646589A GB 207648 A GB207648 A GB 207648A GB 207648 A GB207648 A GB 207648A GB 646589 A GB646589 A GB 646589A
Authority
GB
United Kingdom
Prior art keywords
piece
loudspeaker
branson
ear
rests
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
GB207648A
Other languages
English (en)
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Publication of GB646589A publication Critical patent/GB646589A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H04M1/21—Combinations with auxiliary equipment, e.g. with clocks or memoranda pads
    • H04M1/215—Combinations with auxiliary equipment, e.g. with clocks or memoranda pads by non-intrusive coupling means, e.g. acoustic couplers
    • H04M1/2155—Acoustic coupling
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/6033—Substation equipment, e.g. for use by subscribers including speech amplifiers for providing handsfree use or a loudspeaker mode in telephone sets
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/62—Constructional arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Details Of Audible-Bandwidth Transducers (AREA)
GB207648A 1950-06-08 1948-01-23 Improvements in or relating to amplifying devices for use with telephone apparatus Expired GB646589A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1427050A GB684633A (en) 1950-06-08 1950-06-08 Improvements in or relating to amplifying devices for use with telephone apparatus

Publications (1)

Publication Number Publication Date
GB646589A true GB646589A (en) 1950-11-22

Family

ID=10038122

Family Applications (2)

Application Number Title Priority Date Filing Date
GB207648A Expired GB646589A (en) 1950-06-08 1948-01-23 Improvements in or relating to amplifying devices for use with telephone apparatus
GB1427050A Expired GB684633A (en) 1950-06-08 1950-06-08 Improvements in or relating to amplifying devices for use with telephone apparatus

Family Applications After (1)

Application Number Title Priority Date Filing Date
GB1427050A Expired GB684633A (en) 1950-06-08 1950-06-08 Improvements in or relating to amplifying devices for use with telephone apparatus

Country Status (3)

Country Link
BE (1) BE499477A (enrdf_load_stackoverflow)
CH (1) CH288283A (enrdf_load_stackoverflow)
GB (2) GB646589A (enrdf_load_stackoverflow)

Also Published As

Publication number Publication date
CH288283A (de) 1953-01-15
BE499477A (enrdf_load_stackoverflow)
GB684633A (en) 1952-12-24

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