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Build Your Own Bluetooth Hearing Aid
CloudShape writes "I've been trying to find a way to make a mobile phone work with my hearing aids for some years now, and I finally managed it a few days ago. Although the procedure itself is pretty simple, the surrounding issues are good for quite a bit of discussion."
Imagine the possilbities for bluejacking!
-- Samir Gupta, Ph. D. Head, New Technology Research Group, Nintendo Co. Ltd., Kyoto, Japan.
Bluetooth is an important add-on to cellular technology because as hearing aid users clearly realized right from the start, there's a lot of RF coming out of that little thing! We hear about all of these questionable health risks... why are we even taking the chances?
Can I hear you now? Wait, did I load the kernel module? Hello? DAMN IT!
It is pitch black. You are likely to be eaten by a grue.
You'll actually need that tinfoil hat.
I can't read this article, I'm blind!
What a neat project. I've been thinking about the same problem for a while because my Great-uncle is going deaf. He takes out his hearing aids when he talks on a conventional phone (remember back in the day when you used to be able to get those big bowl-looking things that fit over the ear-piece to help make up for the abscence of the hearing aid?), but using a mobile phone is impossible becaues of the RFI.
He is pretty old, so we would feel a lot more comfortable if he could have a phone with him at all times. I can't wait to try to build one of your devices for him.
... turning to the 3-D map, we see an unmistakable con
Effectively, this solution is working because bluetooth uses a much lower power RF signal so the wire is not interfered with... he's just built himself a custom connection so that a hearing aid can be connected to the bluetooth tranciever.
So really, all that really needs to be on the market for this to be a mainstream solution are A: Bluetooth adapters that connect to the phone and have a standard 2.5 mm output, and then B: an adaptor to convert that to a hearing aid-friendly conector. It'd have the side effect of letting all of us also connect our favorite handsfree piece to the phone by Bluetooth
toothing with your ear piece! ouch.
I found it quite humorous, really, clicking on a page about hearing aides and getting visually yelled at.
That you RTFA. This is /. after all. But if you did you would have seen:
No amount of extension cable will make a wired hands-free usable - the wire always conducts enough RFI to cause trouble, regardless of any filters that might be in place.
So connecting the phone directly to the hearing aid via a wire isn't an option.
SteveM
I don't wear those standard/common ones that go on the ears. Mine is the bone conduction type with a headband since I do not have ear canals. I wonder how difficult it is to do this for this type of hearing aid.
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
I was wondering if this guy has considered selling/giving his idea to the manufacturer of the bluetooth headset. This could always lead to a nice job offer later.
On another note, does anyone know where to get that faceplate for the T68i in the following picture?
http://www.gfern.com/btha/btha-complete.jpg
I have a moderate hearing loss, and have found that using cellular phones with my hearing aides is nearly impossible. I look forward to this technology and hope that it will eventually lead towards my being able to use my hearing aids and cell phone simultaneously. There are a few things that I have found work moderately well to compensate for the interference. I have a clamshell cell phone, a Samsung x-427. The clamshell design helps keep the antenna another couple of inches away from the hearing aide, and its enough to make a conversation tolerable. My old phone was a non-clamshell Nokia, and its interference was horribly bad. My hearing aids also have a background noise canceling feature that, when I turn it on, takes out quite a bit of interference. Unfortunately it also makes understanding conversations harder. I am left with having to take out my aids completely to talk on the phone. its quite annoying. For those of you who wonder exactly what the interference sounds like, check out http://commerce.motorola.com/consumer/QWhtml/acces sibility/hearingAid.html
there are a few .wav files on this page which sound very familiar to me. Imagine those sounds blaring over every conversation on your phone. It gets to be where you just cant tolerate it anylonger.
To my knowledge, only Nokia has an attachment for their phones to allow for use of the Telecoil. Information is at http://www.nokiaaccessibility.com/loopset.html.
If anybody out there has used one of these, i'd love to hear your testimonial on how they work...
Garth
34 posts and not one response on how he was originally designing this for 50 pounds for patentable hardware?!?!? This is /. isn't it?
I once worked for a cell phone company in Phoenix. I'm not a cellular engineer, so the theory and such is a bit over my head, but I was offered a simplified explaination on how the CDMA system worked, and how it differed from other forms of cellular access. This was several years ago, so hopefully I remembered it correctly.
Analog cellular works much like standard radio. A signal is broadcast on a particular channel and your phone negotiates with the cell towers to broadcast on a that channel; each user has a distinct access path. Analog signals also have to broadcast above the noise floor in order to be heard by the tower. I think the FCC limits the maximum power of analog to 4 watts.
Each analog call has to use a single analog phone line. This is somewhat limiting for the cell companies as they need a single POTS voice channel for each cellular connection. This gets very expensive as the number of calls go up.
TDMA is a multiplex scheme. It stands for Time Division Multiple Access. Each phone under TDMA is given a specific "slice" of a channel to communicate on. This allows multiple phones to operate on the same channel at the same time, allowing the carrier to expand the capacities of the cell towers without adding extra land-lines.
CDMA stands for Code Division Multiple Access. Under the CDMA system, each phone communicates with the cell tower and agrees upon a particular part of the spectrum to use, a particular channel in the spectrum, and a compression method. Depending on the compression used, you can squish more calls per channel. CDMA also operates below the noise floor, so a typical CDMA broadcast is in the milliwatt (or lower) range. The power is adjusted several times per second to keep multiple phone signals on the channel from stepping all over each other.
I've probably got some of the particulars wrong, as about 25% of what the engineer said to me was over my head.
There's so little difference between politics and jihad lately...
You didn't mention whether you were aware of an existing technology, but there's something known as an "induction loop".
:D
Being hearing-impaired myself, I obtained an induction loop that jacks into the cell phone. The signal is clear as day. Of course, you have to deal with batteries, but an advantage is, hands-free mode. There's a microphone portion where the cord forks into a 'Y'.
I imagine the local Bell cell-phone store would carry it (that's where I got mine).
Good luck.
spam, spam, spam, spam, e-mail, news and spam.
Some of the brighter /.'ers can check out the wireless communication specs. Some carriers are slowly switching over to the 800/850 band, but not my carrier. They're mostly at 1900MHz. Here's another article that's a bit more informative.
Yea, so: I think it's possible that your phone is on the higher frequencies while the other two aren't. I know for a fact my cell is @ 1900MHz and that i really hate it when people call before 9.
As a bonus, I discovered yesterday that the cordless phones in our house drown out my wifi cable modem. What a trip. Isn't it wonderful how they're both at 2.4GHz.
[Fuck Beta]
o0t!
Can someone clarify one thing for me - why bother with Bluetooth for this application? I'd think it'd be easier just to use a cell phone that has a standard 2.5mm jack.
Take any "hands-free" kit with a microphone in the cable and a 2.5mm connector. Snip off the earpiece, leaving the microphone behind, and replace the earpiece leads with a 3.5mm mono jack. Use the 3.5mm to hearing aid adapter as shown in this story, and you're done.
If you're going to have something clipped to your belt and a big cable, may as well carry the cell phone on your belt and have the wire going directly to the phone instead of a wire to a wireless link.
I have the same problem, but with my GSM phone.
There's nothing like setting your phone down on top of your desk and having your PC speakers or your keyboard synth start shouting in the middle of the night.
DEET-DE-DEET DEET-DE-DEET DEET-DE-DEET. BZZZZZT.
Oddly, my TDMA/CDMA phone never did anything like this.
You know, the thought had never even crossed my mind... thank you for that, it made me laugh!
As mboverload says, I wrote the disclaimer in capitals because everyone seems to do it that way. I'm not sure why, although I suspect it might be so that people can't claim that a disclaimer was "hidden in the surrounding text" or somesuch. If someone could claim that the disclaimer was hidden so they wouldn't notice it, they might just be able to sidestep it on the basis that it hadn't been made clear, and demand damages anyway.
The reason my page doesn't have a clickable contents list with in-page link targets is so that people are forced to start at the top where the disclaimer will be presented to them up front. Mind you, I can't help feeling that it's a shame we live in a day and age where this kind of legal paranoia is necessary...