A hearing Aid Amplifier

[Audioguru]

For the case of acoustics and echo canceller, cant we use a simulation software ?
Can you remember from your stock ?

At first, the echo canceller makes a model of the acoustics of the room when pink noise is played through the speakers and is picked up by the microphones and its frequency response and phases are analyzed and saved. The echo canceller is "adaptive" so it tries to use incoming speech as its signal and makes changes to the model of the room acoustics to make the model accurate if it detects changes to the model.
Cirrus Logic and other manufacturers make echo canceller ICs. Polycom speakerphones use an echo canceller so that they are "full duplex" (you can talk and listen at the same time without having feedback or switching).

[WonderWheeler]

Have a special interest in what they used to call "Appropriate Technology", things that help people in village cultures in developing countries live a bit better, especially.

Could you kindly talk more about it,  "telemedicine " facilities is being popular in the region I have born.

Best Regards
Hasan

Hasan:

"Appropriate Technology" in the US, was a reaction against the 1970s culture that created the "Vietnam War", environmental pollution, and overconsumption and waste of natural resources. https://en.wikipedia.org/wiki/Appropriate_technology  Smart, long haired college students, that were shall we say smokers rather than drinkers, thought that maybe a new type of technology could fix culture. Something that involved village scaled technologies, using methane digestors to produce gas, solar water heating, rammed earth walls, solar electricity, vegitarianism, windmills, democracy, cooperative businesses and other low tech solutions.

The state of California even had an office called OAT, where some friends and I got a small grant to do a video on solar in the 70s.

It later looked like A.T. was just wishful thinking, and right wing polititions took control.... sorta like today, lol

Regardless... a small durable cheap open source hearing aid could do a lot for poor people around the world. Partial hearing loss due to age or an infection.

[Md Mubdiul Hasan]

Dear Sir WonderWheeler,

Thank you to describe things well.
Let me write beside your comments.

"environmental pollution, and overconsumption and waste of natural resources.

Beside "robots" what electronics idea you can imagine for such solution ?

  Smart, long haired college students, that were shall we say smokers rather than drinkers, thought that maybe a new type of technology could fix culture. Something that involved village scaled technologies, using methane digestors to produce gas, solar water heating, rammed earth walls, solar electricity, vegitarianism, windmills, democracy, cooperative businesses and other low tech solutions.

Nice, still those solution is MUST in developing countries.

Regardless... a small durable cheap open source hearing aid could do a lot for poor people around the world. Partial hearing loss due to age or an infection.

A short lasting cheap circuit has good business in my country, I am looking for a good design at least to start. Need to develop a patent  that cant be copied by others.

[Audioguru]

A patent is given to somebody who invents something that has not been done before. Hearing aid circuits are not new and cannot be patented.
You want to design a hearing aid that is CHEAP with poor performance. There are many of them in China, look at Banggood.

[Md Mubdiul Hasan]

Thank you sir 

Hearing aid circuits are not new and cannot be patented.

You might talking a very tinny one, lets see inside.