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)
  • Details Of Audible-Bandwidth Transducers (AREA)
  • Coils Or Transformers For Communication (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 (instruction)
CH (1) CH288283A (instruction)
GB (2) GB646589A (instruction)

Also Published As

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

Similar Documents

Publication Publication Date Title
US2214992A (en) Receiver and transmitter for telephone desk sets
GB858678A (en) Loudspeaking telephone using transistors
US2573438A (en) Electroacoustic transducer set
GB646589A (en) Improvements in or relating to amplifying devices for use with telephone apparatus
GB761169A (en) Improvements in or relating to hearing aids
GB791895A (en) Improvements in or relating to telephone sets
GB620695A (en) Improvements in or relating to amplifying devices for use with telephone sets
CN205305112U (zh) 一种导游扩音器
GB1002983A (en) Apparatus for two-way speech communication
GB664141A (en) Amplification of telephone reception
US2791630A (en) Radio connected system for exhaust sounds of internal combustion engines
GB1324058A (en) Telephone handset
GB662188A (en) Amplification means for telephones
GB929851A (en) Improvements relating to hailing equipment
GB936756A (en) Improvements in or relating to loudspeaking telephone systems
GB909164A (en) Improvements in or relating to loudspeaking telephone instruments
GB638930A (en) Improvements in and relating to radio and intercommunication apparatus and systems
GB655229A (en) Improvements in or relating to operating circuits for moving-coil loudspeakers
GB795144A (en) Improvements in or relating to loud-speaking telephone apparatus
US3404234A (en) Confessional construction
GB823433A (en) Deaf aid apparatus
GB792597A (en) Transducer housing
GB703352A (en) Improvements in or relating to telephone amplifiers
GB787035A (en) Improvements in hearing aids
GB834268A (en) Improvements in hearing aid apparatus