Normal operating conditions:
Ambient temperature 5 ? ~ 40 ?;
Relative humidity ? 80%;
Atmospheric pressure 86kPa ~ 106kPa;
Power supply voltage d.c.1.4V, with a relative error of +5%, -10%.
Appearance and structure
Hearing aids should be fully assembled parts, fixed should be reliable; text, symbols or markings should be clear, accurate, solid; shell may not have significant abrasions, scratches, depression, front edge and burr.
Positive and negative power supply contacts should be effective.
The gain control operation of the hearing aids should be flexible and reliable, and the fastening parts should be free of loosening.
Electro – acoustic performance
Output sound pressure level (OSPL90) at input sound pressure level of 90dB
Shall not exceed 118 + 3 (dB)
- Ambient temperature 5 ? ~ 40 ?;
- Relative humidity ? 80%;
- Atmospheric pressure 86kPa ~ 106kPa;
- Power supply voltage d.c.1.4V, with a relative error of +5%, -10%.
- Hearing aid, suitable for moderate to severe hearing loss.