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PCE
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DIFF Subclass Not Allocatable
H04R

LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K)

Introduced: September 1968

Description

H04R encompasses devices that convert between acoustic signals and electrical signals for sound reception, reproduction, or amplification. This subclass covers loudspeakers and related output transducers, microphones and input transducers, gramophone pick-ups, and acoustic-electromechanical transducers of similar type. It also includes electric hearing aids designed to amplify sound for hearing-impaired individuals and public address systems that project audio to large audiences. Excluded are purely mechanical sound reproduction devices and non-acoustic applications of electromagnetic transducers.

Title

Titles differ between systems:

IPC: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS

CPC: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K)

Full Title

Full titles differ between systems:

IPC:

LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS

CPC:

LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K)

CPC subdivides this area 2x more granularly than IPC with 17 additional codes.

17 codes are CPC-only extensions.

Note: 17 CPC extensions are marked as secondary classification only.

10 shared codes have differing titles between IPC and CPC.

Child Classifications

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