Summary
Mobile phones and hearing aids in the course of using can produce interference between each other; therefore Federal Communications Commission (FCC) requests to test mobile phones and hearing aids electromagnetic compatibility, and grades the risk of interference: T1 - T4, M1 - M4.
National bureau of standards (ANSI) adopts ANSI standard C63.19. According to the regulation of Federal Communications Commission (FCC), mobile phones must conform to HAC compatibility (M3-4 and T3-4).
HAC Test：
1. RF: RF-E frequency electric field, RF-H frequency magnetic field Near field of electric and magnetic field emitted by E and H field miniature probe mobile phone.
When a digital mobile phone is close to a hearing aid, antenna digital pulse of the digital mobile phone will be interrupted by the hearing aid microphone and inductive pickup coil, which affects the function of the hearing aid.
2. T-coil part: the magnetic field of ABM1 sound signal and noise test the magnetic field emitted by a probe mobile phone with T coil.
A digital mobile phone close to a hearing aid causes feedback. If all-digital hearing aids with antireaction, the acoustic interference can be eliminated.
The newly bought HAC test equipment of US is with the best performance in the market and meets the highest requirements of HAC test standards. US is one of the three labs equipped with HAC test equipment in Shenzhen. Otherwise US can provide one-stop service of test and certificate application of RF, SAR and HAC. Certification cycle is shorter than that of other labs which can do SAR or HAC. Customers no longer are upset for shipment because of cycle.
Standards and Regulations
| States | FCC |
|---|---|
| test standards | FCC 47 CFR§20.19; KDB285076 D01; KDB285076 D02; ANSI C63.19-2011; reference appendix。 |
| class requirements | RF：M3-M4（including M1-M4） T-coil：T3-T4(including T1-T4) |
| channels | low, medium and high channel of each frequency band |
| frequency bands | the same as frequency band of mobile phones |
| Note: HAC is not mandatory in other countries. | |
