# Child / Teen tracking devices - don't work??



## shesulsa (Oct 13, 2006)

Some of you know my teenage son is moderate to high functioning autistic and has a tendency to wander at times.  He also can't "read" people to ascertain whether or not they intend him harm, etcetera, so we obtained a GPS tracking device and paid for monthly monitoring from the LifeSafe program through our local Sherriff's office.  

It's not a bad deal ... $25 per month and a cheapie and bulky bracelet which he actually kept on.  The device appears to be of the quality of a happy meal toy watch - the wristband is a broad version of a hospital band and the device itself is about the circumference of a quarter and about an inch thick.  The device is waterproof (or at least it was) and the locater's accuracy is within three feet of the device.  The device is used a lot for Alzheimer's patients and other dementia disorder patients as well.  Many people around the country are getting these devices for their loved ones as an inexpensive piece of mind.  I even did a television spot for this program which not only airs locally once in a while but is also used in the training program for LEOs, EMTs and S&R candidates.

I was given a testing unit to make sure the device was sending signal and every time I tested it (weekly), the indicator received the signal.  A volunteer through the County Sherriff would come out monthly to inspect the device, replace the battery, test it, make contact with my son, etcetera.

Then ... the device stopped working.  I was told it was because we are now swimming in a salt water pool and the salt water degraded the o-ring which kept the device waterproof.  Only problem is that he swam with that device in that pool for a year before the device became compromised.  And after the entire unit was replaced, upon monthly inspection we saw more rust and water in the device.  The tester revealed his device was no longer transmitting.

A handful of weeks ago, my teen ran away and was found several miles from my home on a freeway bridge over the Columbia River.  Search and Rescue happened to be driving on the bridge at the time, drove by him several times and the device did NOT transmit.  *The very incident we feared and which we obtained the device for occurred and the device failed.*

So I've been doing a little looking and found some very insightful information regarding GPS locating and other similar devices.

First, I found an old article from BBC News regarding a locking wristband which looks WAY cooler than the bulky item my son was wearing.  Upon going to the website for that product, I found this: they no longer sell the product.  

Why?

Because GPS is not always the best system to use to locate a person with.


> GPS only tells the person (or child) with the GPS device where they are. It does not tell anyone else (such as a parent or police) where the child is. In order to tell another person where the child is requires some type of communication system such as a cell phone or walkie-talkie connection. It was developed by the military and was designed to locate large objects such as airports, aircraft carriers our buildings. It was not designed to find people inside of buildings.
> There is not a GPS product on the market that is small enough to be worn by a child under the age of 10.
> 
> GPS was designed to identify the coordinates (latitude, longitude and altitude) of objects such as buildings, airports, aircraft carriers, etc.
> ...


Now, there are other products available such as Ionkids, but of course they have only developed product for kids 12 and under for placement on their person such as the bracelet/wristwatch.  This operates on a wireless radio and each unit has its unique frequency.  There are other features which make this device attractive, especially for mothers of multiple children and for inside and VERY local, VERY recent separation.

I bought a parent pager long ago which is a rather neat device - there are two units, one of which clips to a child's clothing, backpack, pocket, etcetera (small, like a car remote) and another on a keychain for the parent.  If child wanders and parent can't find him/her, parent can push a button on his/her remote and the child's pager will emit a constant beeping, allowing the parent to track his/her child auditorally.  This little kit cost me $15.00 about 8 years ago plus the cost of batteries.  In my situation, my son is auditorally sensitive, so the beeping when he wandered worked as a deterrant for him ... at least for a handful of years.

Then there are teen tracking devices for kids who drive and are not disabled.

Of course, there's always the good old cel phone, but when it comes to people like my son, that's not always an option.  And many of these devices are only good up to about 1/4 of a mile.

So before you shell out a ton of dough or start racking up a montly debt, consider several things before you invest in these expensive solutions:

1.  What exactly are my needs?  If you have a young, typical child who happens to be precocious, you might only require a parent pager which can be bought just about anywhere child safety items are sold.  If the child is older, a cheap cel phone might be a better choice.

2.  How effective is the device and reliable the service? 

3.  How far will it track and what information will it give me?

4.  How expensive is it?


----------



## SFC JeffJ (Oct 13, 2006)

Good info and advice.

Thanks

Jeff


----------



## Carol (Oct 13, 2006)

IonKids highlights the negative points of GPS, but it doen't highlight the negative points of its own system.

RF technology is also subject to fade and distortion around an electromagnetic field.  EMF interference is most commonly produced by motors.  Anyone  that has seen an over-the-air TV or Radio signal go haywire when a vacuum is turned on knows what I mean. 

If the child is around a blower motor, microwave oven, hair dryer, floor cleaning equipment, detector circuits (device tag detectors, etc),  _*or inside a car*_...I would be highly suspicious of the device's ability to function within its specified parameters.


----------



## shesulsa (Oct 13, 2006)

Carol Kaur said:


> IonKids highlights the negative points of GPS, but it doen't highlight the negative points of its own system.
> 
> RF technology is also subject to fade and distortion around an electromagnetic field.  EMF interference is most commonly produced by motors.  Anyone  that has seen an over-the-air TV or Radio signal go haywire when a vacuum is turned on knows what I mean.
> 
> If the child is around a blower motor, microwave oven, hair dryer, floor cleaning equipment, detector circuits (device tag detectors, etc),  _*or inside a car*_...I would be highly suspicious of the device's ability to function within its specified parameters.


Another excellent point.  Indeed, RF technology *is* imperfect, in fact I thought it was one reason we were turning to GPS technology.  All of the devices you mention are in wide use every day in virtually every venue.  

So for now, I'm resorting to the old-fashioned hand-holding axiom.  I can still grip tighter than he can pull off fast.


----------



## Kacey (Oct 13, 2006)

I don't have any advice to offer, but I'll be interested to see what people come up with.


----------



## Fionn McCool (Oct 13, 2006)

It'll give NEW meaning to the term "Big Brother is watching"


----------



## still learning (Oct 13, 2006)

Hello, One day they will implant devices for babys and young kids and special needs of older people to locate there bodys.

It will need to be like a GPS unit/radar like devices.  In time these things will improve and be reason cost.

Must be voluntary too!  .......Aloha and thank you for sharing!


----------



## Arizona Angel (Oct 13, 2006)

Don't they have implants for dogs?  How do they work?


----------



## Last Fearner (Oct 14, 2006)

Shesula,

Thanks for bringing up this subject.  I believe it is one that needs further research, and possibly some pressure from concerned parents to get better technology made available.

I have had to confront this issue with my my oldest 8 year old son (a twin who displays characteristics of mild autism).  For lack of better choices, we have always kept a very close eye on him so that nothing tragic happens.  When I was a police officer back in the 1980s, we got a call once that an out of town family was staying at a local hotel near lake Michigan on the St. Joe River.

Their autistic son (about 12 years old) had wandered off.  All of our patrol cars began a pattern search throughout the city.  My partner and I began concentric circles moving further out.  Then we decided to drive a straight line on the main street out of town.  We were flagged down at the city limits by a citizen who had picked the boy up because he saw him walking by himself, and could not respond to questions.  Fortunately, this family got their son back.

My wife and I had an ADT alarm system installed on our home.  24 hours a day, the door alarms are armed so that we will know if our kids open a door and try to leave.  We do not let our children play outside without direct eye contact at all times, even in our fenced in back yard.

A year ago, we took our three boys to a local fair. In the first building, the oldest boy disappeared in a split second.  My wife and I called but he did not answer.  I began to search the crowds in and out of buildings.  I circled back and found that my wife had located him.  He was within a few feet of where we were, but had ducked behind a curtain.  The scare was enough to prompt a search for a locater device.

I had much of the same concerns you brought up about GPS not working well.  I eventually settled on the ION Kids wrist tags because they seemed to suit the purpose we most needed.  I wanted a device that would alert me if he walked away in a crowd, and would send a signal that would help locate him.  I put a wrist tag on each of my kids when we go anywhere.  The parent device keeps track of each of them on a monitor screen that fits in your pocket.  If the alarm goes off, you can turn the device like a compass to locate the direction.  The wrist tag also beeps to alert others.

My problem with the device so far is that the alarm is not loud enough, and it is not perfectly accurate to find the direction.  The wrist tag has two contact points on the under side that sets the alarm off if the tag is removed (a good idea) but, again, the alarm is not loud enough, and it often goes off with false alarms because of movement on the wrist.  Also, it will not work at long distances, but that is not what we use it for.

When my twins were born, they had sleep apnea (they would stop breathing in their sleep until you startled them with a firm touch, or a noise)  The hospital provided us with monitors (after much insistence) which gave us peace of mind.  As they got older, we used a pad in their crib with an "Angel" monitor that would go off if they stopped breathing, or got out of their crib.  These were relatively new devices, and I believe they have started making larger versions for older kids, or adults who need to be monitored.

We need more advanced devices that work out these problems you have mentioned.  Perhaps there is some person of influence, or organization that a number of parents could prompt to do more research and development along these lines.

Any suggestions?

Last Fearner


----------



## Carol (Oct 14, 2006)

There are a few things to keep in mind about any wireless transmission, regardless of what flavor alphabet soup is used.

All transmitters need a source of electrical power to broadcast. No power, no work. Battery issues will fail ANY sort of mobile wireless transmission. The unit MUST have power to generate the airwaves.

All transmitters need a precisely honed oscillator (to make waves in the electric current) and antenna (to a turn the electric waves in to airwaves) to be able to broadcast on a frequency. In a small unit, this could be as simple as the guts of a unit holding a tiny chip (or crystal) to serve as the oscillator and a precise metallic element to serve as antenna. Without either of these, the transmitter won't work.

What this means to you - mechanical issues (impact, corrosion, extreme temps) will fail ANY sort of wireless device. 

Neither a power failure or a mechanical failure is likely to have any sort of warning sign.

All wireless devices are subjected to interference of some sort. GPS won't work in caves or caverns, agreed. RF devices work poorly in caves and caverns. Many folks don't live near caves or caverns.  Many folks DO live near....basements. There is NO wireless device that works effieciently when the receiver or the transmitter is in a basement, unless the receiver and the transmitter are both in the basement. 

The cell-phone dropping analogy as a reason why cellular contact doesn't work is flawed. Cellular is one of the stronger ways of transmitting GPS data as the cellular network is the farthest-reaching, most-used, most-demanded, and most profitable wireless network in the country. When a cell call drops, most people hit "Send" again and are reconnected with their party. Unless the child was in a null or dead area, a drop in cell coverage may only be seen as a momentary blip in the data. 

Aside from suggesting that one should purchase such a device from a store with a generous return allowance, from an engineering perspective the suggestions that I have are not going to be popular with kids or parents. But, here goes nothing...

A wireless device needs power. Power comes from a battery. Up to 85% of the weight of mobile wireless devices is battery weight. A bigger, bulky device may be uglier to wear, but it may have a better source of power, resulting in better reception/transmission capabiilities or more reliable battery life. That's probably not going to be popular with kids.

If a parent believes this is a critical device, then it may be best to adopt a model used in Aviation and other industries with mission-critical equipment. If the funtioning of the device is critical, that means the device can't die. Don't wait for it to die. (Hint: kids break things!) Replace it every X months, whether it needs it or not. That's probably not going to be popular with parents. 

But, from a tactical standpoint...both the child and the parent are best served from a device that functions as well as it can.


----------



## Brian R. VanCise (Oct 14, 2006)

Carol Kaur said:


> There are a few things to keep in mind about any wireless transmission, regardless of what flavor alphabet soup is used.
> 
> All transmitters need a source of electrical power to broadcast. No power, no work. Battery issues will fail ANY sort of mobile wireless transmission. The unit MUST have power to generate the airwaves.
> 
> ...


 
That sounds like good solid advice Carol!  Testing of the equipment and replacing batteries or the entire bracelet, etc, should be done regularly.  Eventually all of the bugs will get worked out with these new tracking devices.  Even then I doubt that they will be one hundred percent right every time but they do have the promise to be more efficient than anything else we currently have.


----------



## Ninjamom (Oct 15, 2006)

Carol Kaur said:


> ......A wireless device needs power. Power comes from a battery. Up to 85% of the weight of mobile wireless devices is battery weight. A bigger, bulky device may be uglier to wear, but it may have a better source of power, resulting in better reception/transmission capabiilities or more reliable battery life. That's probably not going to be popular with kids.


If we're going with ideas/theories for others to test, why not use an alpha-voltaic or beta-voltaic cell?  I think these are what're used in pacemakers, which need to be small, and also have an extremely critical need to be failure-resistant!  They will be more expensive, but I think they could work.



> If a parent believes this is a critical device, then it may be best to adopt a model used in Aviation and other industries with mission-critical equipment. If the funtioning of the device is critical, that means the device can't die. Don't wait for it to die. (Hint: kids break things!) Replace it every X months, whether it needs it or not.


Actually, this is an excellent idea, and one that can be a little less exensive with one small modification - in avionics, they don't just automatically replace critical parts every X months, but for those things that are truly mission-critical, they use redundancy.  If you're planning to buy a new unit every xx months anyway, why not just have your child wear two at the same time?  Then you don't buy the replacement in xx months, but you buy one replacement when the first unit breaks.

My thoughts: I think any cellphone will currently provide most of the functions that are needed in these cases.  If the cell phone is on, the holder can be tracked to the closest cell tower, and if the phone has GPS, the exact location can be read, all passively.  The question is how quickly/efficiently can this available information be communicated from and through law enforcement agencies?  Accessing this information to help wander-risk individuals will require a change in current law.


----------



## Jonathan Randall (Oct 16, 2006)

Ninjamom said:


> If we're going with ideas/theories for others to test, why not use an alpha-voltaic or beta-voltaic cell? I think these are what're used in pacemakers, which need to be small, and also have an extremely critical need to be failure-resistant! They will be more expensive, but I think they could work.
> 
> Actually, this is an excellent idea, and one that can be a little less exensive with one small modification - in avionics, they don't just automatically replace critical parts every X months, but for those things that are truly mission-critical, they use redundancy. If you're planning to buy a new unit every xx months anyway, why not just have your child wear two at the same time? Then you don't buy the replacement in xx months, but you buy one replacement when the first unit breaks.


 

Yes, but are those batteries of sufficient current to run such a device?

Also, Aircraft have SIGNIFICANTLY higher budgets. Heck, some parts of an aircraft cost more than a family's budget for a year.

Still, great idea on the cell phones. We do need to take a serious look as a society on these recent advances in technology and how we are going to use them to help those who cannot help themselves.

Good post.


----------



## Hand Sword (Oct 16, 2006)

I think, no matter our feelings, they are going to come into use, if not, already. The fact that they are being discussed here, and other places shows a popularity rising, when it would've been laughter and dismissal. Let's make it safe, and make it work, as best as possible, since we are moving that way, and what's on the line is VERY SERIOUS, and precious.


----------



## shesulsa (Oct 16, 2006)

Ninjamom said:


> My thoughts: I think any cellphone will currently provide most of the functions that are needed in these cases.  If the cell phone is on, the holder can be tracked to the closest cell tower, and if the phone has GPS, the exact location can be read, all passively.  The question is how quickly/efficiently can this available information be communicated from and through law enforcement agencies?



I've been told that the cell holder must be in an active call for triangulation to be possible.  Carol? Anyone?



> Accessing this information to help wander-risk individuals will require a change in current law.


You're most likely correct as this is currently voluntary and subscription-only.


----------



## MJS (Oct 16, 2006)

shesulsa said:


> I've been told that the cell holder must be in an active call for triangulation to be possible. Carol? Anyone?


 
We have a GPS feature at work.  When someone calls 911 from their phone, a general area of where the person is, comes up on the screen, but it does not pinpoint an exact location.  This is how our system works, so I can't speak for other versions out there.  A cell phone provider can also be contacted, however, as you said, the person must be on an active call.  Again, this gives a general area.  Also, I'm not sure if just anyone can call the cell provider and ask for a location.  When we call, we still have a ton of questions to answer, and a form to fill out, and this is a Police Dept. using this, so I am not sure if its possible for the general public.

Mike


----------



## Carol (Oct 17, 2006)

Jonathan Randall said:


> Yes, but are those batteries of sufficient current to run such a device?


 
No they aren't.  Atomic batteries have a tremendous amount of promise when used as implanted biomedical devices due to their high reliability and long life.

However, in order for alpha-particle or beta-particle emission to be possible, the core of the battery must consist of radioactive material.  There is shielding for the small atomic batteries that are implanted in the body, I'm not sure what challenge a larger battery would place. 

The isotopes used in atomic batteries cannot be used in nuclear fission - in other words, they can't be used to make a bomb.  However, they are toxic, sometimes highly toxic.  The question then becomes...what amout of radioactive material is safe to be freely distributed in to the public?

In the human body, the amount of radioactive material is very small and it's protected by the body.  (its unlikely that a person would be cut open for the radioactive isotopes in an atomic battery).

But for a device in common use...the radioactive material would be behind a metal casing that would be accessible by some type of tool.  That is not a safe scenario at the moment, I'm afraid.


----------



## Carol (Oct 17, 2006)

shesulsa said:


> I've been told that the cell holder must be in an active call for triangulation to be possible. Carol? Anyone?


 
That is incorrect. 

Triangulation can be made from the RF signals of non-GPS phone long as a call has been made from the phone.  It is not easy, it is not exact, and it is requires quite a bit of manpower to do.  Data that reveals where a cellular subscriber is located is protected under CALEA (Communications Assistance to Law Enforcement Act), but it has been accessed before.  There was a recent case about a kidnapped girl who text-messaged her mother and was traced down using this information.  This is generally only done if it is known that the person is in peril.

The success of finding someone depends on how stationary the person is.  Someone stuck in a snowbank has a greater chance of being found than someone out riding a bike.

Naturally, the more information the caller gives about their location, the easier it is to pinpoint where they are.

The GPS technology in cell phones is a balance between performance and cost-effectiveness.   It is not as precise as the units that track over-the-road truckers, for example.   However, it is more precise than triangulation of RF emissions.

As per CALEA, GPS cell phones in the US must ONLY transmit GPS data if a call is made to 911.

If a person has a GPS phone but does NOT call 911, the only way they can be found is if the RF signals are triangulated.



MJS said:


> We have a GPS feature at work. When someone calls 911 from their phone, a general area of where the person is, comes up on the screen, but it does not pinpoint an exact location. This is how our system works, so I can't speak for other versions out there. A cell phone provider can also be contacted, however, as you said, the person must be on an active call. Again, this gives a general area. Also, I'm not sure if just anyone can call the cell provider and ask for a location. When we call, we still have a ton of questions to answer, and a form to fill out, and this is a Police Dept. using this, so I am not sure if its possible for the general public.
> 
> Mike


 
That information is protected under CALEA.  It is not available to the general public.


----------



## MJS (Oct 17, 2006)

Carol Kaur said:


> That is incorrect.
> 
> Triangulation can be made from the RF signals of non-GPS phone long as a call has been made from the phone. It is not easy, it is not exact, and it is requires quite a bit of manpower to do. Data that reveals where a cellular subscriber is located is protected under CALEA (Communications Assistance to Law Enforcement Act), but it has been accessed before. There was a recent case about a kidnapped girl who text-messaged her mother and was traced down using this information. This is generally only done if it is known that the person is in peril.
> 
> ...


 
Carol,

If I'm reading this right, are you saying that as long as the phone is on, a signal can still be picked up, even if they're not on an active call?  If this is so, I'd imagine if they shut it off, a signal is going to be lost?  



> The GPS technology in cell phones is a balance between performance and cost-effectiveness. It is not as precise as the units that track over-the-road truckers, for example. However, it is more precise than triangulation of RF emissions.


 
GPS was installed on all of the police cars.  Its amazing how accurate that system is. 

Mike


----------



## Carol (Oct 17, 2006)

MJS said:


> Carol,
> 
> If I'm reading this right, are you saying that as long as the phone is on, a signal can still be picked up, even if they're not on an active call? If this is so, I'd imagine if they shut it off, a signal is going to be lost?


 
Yes and no.

Yes because...

Of all the people in the country that have a cell phone...the vast majority of them are in a location where the phone, if powered on and idle,  is constantly in contact with more than one tower.  And yes, if the phone goes dead, the keep-alive signal is lost.

However, this is typically NOT what is used to track down a person in peril.

Cellular companies sell a commodity - minutes of airtime.  Without those minutes, the company would not exist and people like me wouldn't have a job.   The cell companies guard their commodity against loss and fraud, and also look for areas where there is additional demands for service.

One of the ways that they can watch for loss, fraud, or demands for a new area of coverage, is monitoring patterns of signal strength when a subscriber is on a call.  Why is this done only when a subscriber is on a call?  Because when they are on a call they are actually USING the network...and doing something that results in income for the company.

As a result, when someone is actuall ON a cell phone, using minutes, there is a lot more data attached to the company's call records than if the phone is lying idle, not being used.  In many cases, the signal strength of an active call in reference to its respective tower is encoded in to a call detail record.  

It is this encoded data that is analyzed by engineers in conjunction with law enforcement.  As long as there is data that has been captured, this can be used to perform a rough triangulation even after the caller has hung up or even had the batteries of their phone die.

This was how this  kidnapped girl was found.

Legally, this is very difficult as it involves getting permission to break federal law.  Technolgically this is very difficult as there must have been enough data from an active call to be able to make a triangulation, and even then the triangulation only shows an approximate area.

But...triangulation  is _possible..._even if the person runs out of battery power.

Pretty cool, isn't it?


----------



## Carol (Jan 4, 2007)

Here is something else on the subject of tracking devices:  a tracking device, complete with a panic button, has been embedded in a pair of shoes.

Another website believes the shoes will be available for sale in a month or so.

http://blog.scifi.com/tech/archives/2007/01/03/gps_shoes_come.html


----------



## BrandiJo (Jan 4, 2007)

the USB one is kinda creepy... i carry mine with me constantly id hate for my parnets to know everywhere iv been and at what time i was there​


----------



## CuongNhuka (Jan 4, 2007)

Arizona Angel said:


> Don't they have implants for dogs? How do they work?


 
They work my having memory. Our cat has one (they work with any animal). It has her name, or moms name, our address, and a few other details saved onto it. It's set up like a word doc. It isn't so much to help find your pet, but to help your pet get returned to you if found.

and good luck with your son shesulsa.


----------



## shesulsa (Jan 4, 2007)

CuongNhuka said:


> good luck with your son shesulsa.


Thank you. :asian:


----------



## wesley (Jan 4, 2007)

i must say that, parents who think they can track their teen's in such a way are asking for trouble...just about any teen in this day and age has a greater understanding of these types of tech than their parents...therefore..can figure out ways to fool/disable these devices.
all the cell phones i've seen with them in it have a menu with which it can be turned off anyways. 
most people dont realize that teens are fairly smart when it comes to this sort of thing, afterall, finding ways to escape your parents has been a teen priority for thousands of years anyways.lol


----------



## CuongNhuka (Jan 4, 2007)

wesley said:


> i must say that, parents who think they can track their teen's in such a way are asking for trouble...just about any teen in this day and age has a greater understanding of these types of tech than their parents...therefore..can figure out ways to fool/disable these devices.
> all the cell phones i've seen with them in it have a menu with which it can be turned off anyways.
> most people dont realize that teens are fairly smart when it comes to this sort of thing, afterall, finding ways to escape your parents has been a teen priority for thousands of years anyways.lol


 
True... but what you may or may not have realised is something about Shesulsa's son. He's autistic. So her being able to track him may be whats best for him. From her story it sounds like he never bothered to try to take it off. And if you say something about how I wouldn't know, I'm 16.


----------



## Ninjamom (Jan 12, 2007)

On the issues of size and power:

This article just hit the news, describing how the US Government has warned classified military contractors about transmitters found hidden inside fake coins.  I recall reading about similar 'spy technology', the idea being that you don't need a big battery or a large power source, if you use a burst transmitter.  Think of high-power emergency beacons, or even the intermittent setting on your windshield wipers.  Both work by having a relay on a capacitor.  Charge is stored slowly from a low power source, then released in a burst.  If all you are interested in is providing a burst of information that includes location, it would not require a large power source at all.

Also, you don't need a large transmitting antena, as long as you have a large receiving antena.

Anyway, as a safety measure, I think it would be great to get cell phones with *an optional feature that may be turned on/off by the user *that provides an emergency locator beacon, and just flashes out the GPS location with a short transmission burst.


----------



## Carol (Jan 12, 2007)

Ninjamom said:


> On the issues of size and power:
> 
> Also, you don't need a large transmitting antena, as long as you have a large receiving antena.


 
Size doesn't matter in that way.

The size of an antenna and its elements are shaped to match the size of the wavelength (or a fraction thereof).  Satellite signals = small wavelength = small antenna.   The elements of a GPS antenna are typically 2 mm in size.

What does matter is positioning of the antenna.  An antenna mounted to a tower on top of a tall building is generally going to result in better transmission/reception than an element in someone's shoe.  The height of the building seperates the antenna from the miscellaneous chaff that causes interference.



> Anyway, as a safety measure, I think it would be great to get cell phones with *an optional feature that may be turned on/off by the user *that provides an emergency locator beacon, and just flashes out the GPS location with a short transmission burst.


 
Many current cell phones offer such a feature.  It cannot be turned on and off like a light switch....however....when enabled the GPS tracking feature is activated during a call to 911 (and only 911).


----------



## Ping898 (Feb 9, 2007)

Gerogia - perhaps a new way to find your son in the not too distant future....

http://news.yahoo.com/s/ap/20070209/ap_on_hi_te/gps_sneaker



> Engineer: GPS shoes make people findable
> 
> MIAMI - Isaac Daniel calls the tiny Global Positioning System chip he's embedded into a line of sneakers "peace of mind." He wishes his 8-year-old son had been wearing them when he got a call from his school in 2002 saying the boy was missing. The worried father hopped a flight to Atlanta from New York where he had been on business to find the incident had been a miscommunication and his son was safe.
> Days later, the engineer started working on a prototype of Quantum Satellite Technology, a line of $325 to $350 adult sneakers that hit shelves next month. It promises to locate the wearer anywhere in the world with the press of a button. A children's line will be out this summer.
> ...





Expensive now but with luck prices will go down in the future....


----------



## Infinite (Feb 9, 2007)

http://www.engadget.com/2005/12/15/more-on-loc8tor-personal-tracking-system/

So this would alert if he left the range of your house.

You could throw it in a shoe or buy a few and put them on jewlery or some other object. Most (if memory serves) Autistic children have a favorite item they carry everywhere if he does this would be a good thing to add this too.

It isn't perfect but at least you have a proximity warning if he decides to move further away then you expect.

--Infy.


----------



## shesulsa (Feb 9, 2007)

Wow! Good info, guys! Thanks!!


----------



## Infinite (Feb 13, 2007)

Hey! I just found this on CNN

http://www.cnn.com/2007/TECH/ptech/02/13/gps.sneaker.ap/index.html

Call this man explain your situation and ask to trial the kids shoes.


--Infy


----------

