Hearing aids can be a very expensive item, and also technically interesting to some developers in the chase to deliver clearer voice to the user with a minimum of background and unwanted noise. One example of this drive for a better design has been documented by Instructables user ojoshi, who has described their Arduino-powered hearing aid with several functions to help the end user.
With an external series of preamps, programmable filters and programmable amplifiers the device can be set to one of several modes, including user-controlled amplification, a conversation mode to help focus on voice, and the settings can be stored for later recall by the user. The circuitry amplified the incoming signal, splits it into four frequency bands and then recombines the signals for the end user in the required manner.
This is an interesting use of analogue electronics, audio work an an Arduino, so to learn more check out the project Instructable. And for more, we're on twitter and Google+ - so follow us for news and product updates as well.
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