GB374973A - Improvements in telephone systems - Google Patents

Improvements in telephone systems

Info

Publication number
GB374973A
GB374973A GB8845/31A GB884531A GB374973A GB 374973 A GB374973 A GB 374973A GB 8845/31 A GB8845/31 A GB 8845/31A GB 884531 A GB884531 A GB 884531A GB 374973 A GB374973 A GB 374973A
Authority
GB
United Kingdom
Prior art keywords
loud
speakers
march
class
telephone systems
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
GB8845/31A
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 GB374973A publication Critical patent/GB374973A/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
    • H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
GB8845/31A 1930-03-22 1931-03-23 Improvements in telephone systems Expired GB374973A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH374973X 1930-03-22

Publications (1)

Publication Number Publication Date
GB374973A true GB374973A (en) 1932-06-23

Family

ID=4513540

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8845/31A Expired GB374973A (en) 1930-03-22 1931-03-23 Improvements in telephone systems

Country Status (2)

Country Link
BE (1) BE378432A (enrdf_load_stackoverflow)
GB (1) GB374973A (enrdf_load_stackoverflow)

Also Published As

Publication number Publication date
BE378432A (enrdf_load_stackoverflow)

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