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Magnetic Induction Technology Headset Reviewed
Semi-Anonymous Coward writes "The first review of a wireless headset using Magnetic Induction technolgy has been posted at mobile technology website MobileBurn. The reviewer mentions that the technology provides almost 'crystal clear' phone conversations, which is better than most Bluetooth headsets he has used. The magnetic induction technology creates a 'bubble' around the user which increases the security of their communications. Is this the replacement for Bluetooth in Audio applications? It certainly looks like it..."
I always wondered why this effect wasnt exploited more often for short range comm. So easy in the lab to take your poorly designed digital circuit and just put an oscilliscope near and and walla, theres the data on your circuit, no modulation or other assorted rubish.
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No matter how thin you slice it, its still baloney.
The manufacturer's web site seems to be claiming that this gives some privacy due to the use of near field magnetic induction. However, magnetic field antennas (i.e. AM broadcast band ferrite loop stick antennas) are used commonly to receive signals. It seems that all one need do is make a loop antenna sensitive to the 13.5 MHz frequency used and you could listen in with a shortwave receiver. Unless, of course, they encrypted the signal.
Do us a favour, stop posting "reviews" hosted from the products own websites.
ACMD eht detaloiv evah uoy
The big question is security. Magnetic induction technology is in widespread use already - post-office counters, public address systems and ticket booths are often fitted with inductive loops for the benefit of hearing-aid users, who can pick up the sound from them directly by switching their aids to a special setting.
:-)
The article doesn't say, but one hopes that the manufacturers have built some reasonably sophisticated security into their system - if not, then eavesdropping devices for them are already in widespread use.
I'm not sure I really want a magnetic field around my head. I recall an episode of "Scientific American Frontiers" (no energy to find link, Alan Alda, PBS, etc) with a physiologist investigating the brains ability to adapt and allocate bored portions of the brain for other tasks. They blinfolded a volunteer and showed how her optical cortex began processing tactile rather than visual inputs.
...Likes! brain!"
THEN, they used a magnetic field (applied via wand to the back of her head) to essentially erase/shut off/disable this new function. They were quite casual about it, and it was pretty obvious that the erasure was well established.
So, count me out!
[Kent Brockman] "...ahem....Little girl
Most phones are already fitted with an induction coil in the handset - these are there to work with hearing aids (I wear one myself). In older phones, and certain new-ish payphones these induction coils work extremely well - good clear sound, and they couple with the hearing aid well. But the vast majority of modern phones - including those labelled "hearing aid compatible" have induction coils that barely work at all. It's impossible to find a phone that works with a PABX system that has an adequate induction coil that works with a hearing aid. I looked far and wide and tried a few devices, but in the end I had to give up - there is literally no such thing as a phone or device that works with a PABX system that approaches the effectiveness of my home phone, in terms of being able to hear it. There is a third-party handset sold for this purpose (IIRC, the brand is "Walker"), but its induction coil is very weak too -- all they did was to to put a very cheap and nasty amplifier in the handset - and we all know exactly how much THAT benefits the sound quality. It would make my life a lot easier to be able to find a phone for the office that I can use. I wonder if this new gizmo could be adapted somehow...
Yes. I need more crap. I need a selection of 50,000 different headsets because damnit, a telephone is just *too* heavy to pick up with my hand. I need to buy some overpriced plastic crap because I'm just that lazy. Really. Sell me some more shit, /. I'm also looking for a device that'll hold my dick while I pee, because I really can't be bothered with that much effort.
This is a lot more interesting than you might think. H (near) field communication is really unexplored in the commercial world. It is rather limited in range (meter or two) and for the most part it is rather ignored in EMC testing (Electro-Magnetic Compatability [read FCC testing]). If you want to see a cool example of H field interference dig up two 10 year old 20" monitors and put them side by side and watch the wicked interferance. Even if you wrap the monitors in a grounded wire mesh you will still see interferance because the problem is a magnetic H field not an E field (RF) signal. To kill the interferance you need to use a Mu Metal shield (or one heck of a lot of iron). Of course, one application's interferance is another signal. If you are really carefull about building your H field and not generate much E field it would be rather secure from evesdropping outside of 4 or 5 meters.
Heh, you should see what happens when you put aluminum cans in a high power magnetic induction device... Whew, found some images at TeslaMania for before and after...
When I was in school, the prof brought one of these into lab one day, and he was using it to railgun things across the room... They kept it locked up because some years before a student thought it would be funny to wrap a banana in foil and stick it into the machine, and it worked... picture a in your head a fine mist of burnt banana covering a good portion of a large freshman electronics lab, and that's close to the result. This site explains why with pictures.