FR2278213A1 - Telephone handset with handgrips surface increased by holes - shaped to absorb and scatter sound waves to reduce feedback - Google Patents

Telephone handset with handgrips surface increased by holes - shaped to absorb and scatter sound waves to reduce feedback

Info

Publication number
FR2278213A1
FR2278213A1 FR7442363A FR7442363A FR2278213A1 FR 2278213 A1 FR2278213 A1 FR 2278213A1 FR 7442363 A FR7442363 A FR 7442363A FR 7442363 A FR7442363 A FR 7442363A FR 2278213 A1 FR2278213 A1 FR 2278213A1
Authority
FR
France
Prior art keywords
holes
sound waves
telephone handset
handgrips
absorb
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.)
Withdrawn
Application number
FR7442363A
Other languages
French (fr)
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.)
Deutsche Telephonwerke und Kabelindustrie AG
Original Assignee
Deutsche Telephonwerke und Kabelindustrie AG
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
Priority claimed from DE2433824A external-priority patent/DE2433824B2/en
Priority claimed from DE19742453185 external-priority patent/DE2453185C2/en
Application filed by Deutsche Telephonwerke und Kabelindustrie AG filed Critical Deutsche Telephonwerke und Kabelindustrie AG
Publication of FR2278213A1 publication Critical patent/FR2278213A1/en
Withdrawn legal-status Critical Current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
    • H04M1/20—Arrangements for preventing acoustic feed-back

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Telephone Set Structure (AREA)

Abstract

The telephone handset has the surface area of its handgrip increased to reduce the effects of acoustic feedback. This surface between the microphone and loudspeaker cups is shaped according to geometric laws of reflection so that the sound waves are absorbed or scattered and thereby reduced in intensity. The increase in area is achieved by boring holes in the handgrip. The holes may have cylindrical or tapering walls. The sound is scattered by irregular inclined surfaces on the handset. The holes act as absorbers and the irregular inclined surfaces as scattering regions.
FR7442363A 1974-07-11 1974-12-20 Telephone handset with handgrips surface increased by holes - shaped to absorb and scatter sound waves to reduce feedback Withdrawn FR2278213A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE2433824A DE2433824B2 (en) 1974-07-11 1974-07-11 Sealable handset for telephone equipment composed of two housing halves
DE19742453185 DE2453185C2 (en) 1974-11-07 Arrangement for telephone handsets with enlarged gripping surfaces

Publications (1)

Publication Number Publication Date
FR2278213A1 true FR2278213A1 (en) 1976-02-06

Family

ID=25767417

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7442363A Withdrawn FR2278213A1 (en) 1974-07-11 1974-12-20 Telephone handset with handgrips surface increased by holes - shaped to absorb and scatter sound waves to reduce feedback

Country Status (1)

Country Link
FR (1) FR2278213A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0595534A2 (en) * 1992-10-28 1994-05-04 AT&T Corp. Compact loudspeaker assembly for telephone set

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0595534A2 (en) * 1992-10-28 1994-05-04 AT&T Corp. Compact loudspeaker assembly for telephone set
EP0595534A3 (en) * 1992-10-28 1996-04-24 American Telephone & Telegraph Compact loudspeaker assembly for telephone set

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Legal Events

Date Code Title Description
ST Notification of lapse