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You can use Global Patent Index (GPI) to carry out detailed searches in the EPO's worldwide bibliographic (DOCDB), legal event (INPADOC) and full-text data sets, and download or visualise the search results for statistical analysis.

Current content: 159 823 134 patent documents

This week's update (15/11/2024 12:00 CET):

143 307 new documents added

1 003 170 documents amended

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EP 0390758 A2 19901003 - A microphone amplifier for contact microphones.

Title (en)

A microphone amplifier for contact microphones.

Title (de)

Kontaktmikrophon-Verstärker.

Title (fr)

Amplificateur pour microphone de contact.

Publication

EP 0390758 A2 19901003 (EN)

Application

EP 90850090 A 19900305

Priority

SE 8900759 A 19890306

Abstract (en)

To improve the clarity of speech recorded using a contact microphone (10), it is proposed that preferably after passage through a pre-amplifier (11), the electric signal from the contact microphone (10), shall be subjected to a treatment for modifying its amplitude in a first signal processing unit (12) and to a treatment for modifying its spectral structure in a second signal processing unit (13).

IPC 1-7

H04R 1/14; H04R 3/00

IPC 8 full level

H04R 1/46 (2006.01); H04R 3/00 (2006.01)

CPC (source: EP)

H04R 1/46 (2013.01); H04R 3/00 (2013.01)

Designated contracting state (EPC)

AT BE CH DE ES FR GB IT LI NL SE

DOCDB simple family (publication)

EP 0390758 A2 19901003; EP 0390758 A3 19911113; SE 466377 B 19920203; SE 8900759 D0 19890306; SE 8900759 L 19900907

DOCDB simple family (application)

EP 90850090 A 19900305; SE 8900759 A 19890306