Cell Phones.. did you know??

[snowdance]

For those that live in areas where you have cell phone service all the time that are going to travel to areas with little or no service like where we live did you know.. Many times your phone will show no service but repeater stations for fire, police,ect will pick up a 911 call. So even if you show no service try it..
Did you know an old cell phone with no service will call 911. We have used them for years on our motorcycles, backpacking ect where we can not lock them up. We just keep them charged up. If some one steals them they just get and old phone with no service. This way people that do not have cell phones can pick up an old one from family or friends and be covered by 911. But if you do use one do it only if really needed as you will have to explain why you are using a phone with no service. Give them you home phone and address ect. Seems even some of the 911 operaters do not know it works. But we have used them several times over the years.

[wa8yxm]

Of course.. If you are a SMART traveler, you do not limit yourself to just one way to call out.

I have cell phone

CB

HAM radio Extra Class (All bands/modes) with 100 watts of power into a 100' wire on 80 through 10 meters, and 100 into a quarter wave on six, a J pole on 2 and 50 into a 5/8 on 70cm.

Odds of my being able to yell for help.. Very high. But the poor guy who answers my call might not be in the United States 🙂

[FOREVER_FREE]

If you are in an area where you have no reception you better keep it on a charger or turn it off altogether cause if you don't that little sucker will search and search until the battery is dead. Then you can't call anyone. Best wishes to ya'all and happy RV'ing. 🙂

[SCVJeff]

I used the term 'modulation' vs. CODEC, but all same-same. Now we're getting somewhere.. There is mis-information from the OP on many different levels; the ability to tie directly into law enforcement comms systems is obviously false. Now to the point that any disconnected cellphone can connect to 911 services is only partially true and limited by the coverage of the carrier from wence it came for all the reasons John defined, if not also the age of the phone.

[wa8yxm]

There is a bit of confusion in the original post.

Your cell phone can not connect to police towers unless the police are spending money I don't know about.

But my cell phone has the ability to connect to towers belonging to a numnber of carriers,, So does yours.. However depending on who your pay your money to it may not be AUTHORIZED for this or that tower... For example it might work on AT&T towers but not T-Mobile (or the other way around) or Century CelluNet towers but not .. Well you get the idea.

Now my phone can work with AT&T, T-mobile and CCN and several others.. But unless my cell company has an AGGREMENT with them, the phone is not authorized to place (or receive) calls on all those towers.

The phoen is compatable with the tower, Just not authorized.

But a 9-1-1 call, by law, the tower HAS to process it, (If it is has the proper codecs for your phone).

That said. Verizon, AT*T/T-Mobile and Sprint/Nextel/Virgin all use different codecs. (Grouped as per the way I typed it)

Any phone that works on a T-Mobile tower can call 9-1-1 on an AT&T tower if that's all there is. Roaming agreement or not (And the other way around).

But Verizon used a differen codec so those towers will not take my calls under any conditions.

[SCVJeff]

Almost....not all cellphones are cross compatible across other systems.. The only time that what you describe is a sure thing is if you are either on the primary carrier, or a 2nd tier like Net 10, Boost, etc. that buys their airtime from the primary carrier.. But one thing is for sure: CDMA won't work on a GSM system, and vice versa. Then there is the issue of exclusive bands.. Even if the modulation is the same on another system, the bands used on various systems are MILES apart by several hundred MHz, and the emergency phone, while GSM on a GSM system may simply not be capable of talking on the competitors system. Personally I would never ever rely on an old deactivated phone to save my life. I'll grab the oil' trusty 2mtr HT 1st... 🙂

The only true flat statement in this thread is that 911 will work on deactivated phones PROVIDING there is cell service, and its compatible with the phone. I still don't buy the "repeater" story unless someone can show a link explaining technically how it works.

[msmith1199]

wny_pat wrote:

YC 1 wrote:

dave54 wrote:

YC 1 wrote:
Repeaters for police and fire will not pick up cell phone signals. If you are meaning their actual communications channels.

They use different frequencies and modulation techniques.

A separate antenna connected to different base unit on the same tower will receive 911 calls. Not too common yet, but increasing in mountainous rural areas.

Can you explain this a bit more please. Some new piece of communications equipment on the market?

Cell phones do not connect to 911 dispatch centers via their towers or radios. They connect via phone lines. The cell towers and vendors send that information via their infrastructure.

Inquiring minds also want to know about this too. In my humble opinion, it is going to be routed thru the cell phone intrastructure before it gets to the 911 center, and not the 911 tower. It is possible that the cell phone service has provided a small repeater transceiver, but I know nothing about that. And just less than a year ago things in California's 911 system were not all that wonderful: http://www.cnn.com/2010/TECH/mobile/09/08/emergency.numbers/index.html

Also got me curious too so I did some research. I'm retired law enforcement and never heard of a cell phone being able to call 911 while it was in an area with no service. The only thing I could find on this is that if you don't have coverage from your own provider and you dial 911, that your phone should roam and search for any other provider and send the 911 call through them. So your phone may show no service, but if you are in the range of any other cell provider you can still make a 911 call. But this is all within the cell providers and not on the law enforcement network.

[Just_Jeff]

I think it's true. I'm looking at my old Windows Phone right now that has no active account associated with the sim card. On the phone icon it says "Emergency Only" instead of "No Service."

[ddndoug]

wa8yxm wrote:
Yup, that was my phone number we are talking about.

wa8yxm - Thanks for your service to the community!


Doug

[jamnw]

Lets just say for half a second that this is possibly true. Why in the world wouldn't that information be disseminated to the public by your local governing agency instead of some email/forum post?

I've worked in telecom for 15 years, and worked in and around some 911 centers. I have heard of the 911 text coming online, but not this.

Now I'm not saying its not true. I just don't believe it, that's my opinion and I'm sticking to it.

[wa8yxm]

Do you know: As a matter of fact yes I did.. You see, the phone number for the office I used to work in is all over this thread.. All 3 digits of it.

It happens to be a federal law.. Any carrier receiving a 9-1-1 call has to send it to the nearest (or proper) call center.

So, let's say your phone is authorized on Carrier A, but A has not roam agreement with B. but only B covers the area where you happen to be pressing SEND, if it's 9-1-1 B has to transport the call.

Or if its a pre-paid out of minutes.. Same thing, No charge for 9-1-1 it does not add to or subtract from your minutes.

PLEASE... When calling 9-1-1 be prepared to tell the ESO (emergency Services Operator) WHERE you are.. He (or she) may need to forward the call.

One (slightly laundered and way shortened call)

Phone: Ring
Me: State Police
Caller: I'm at the corner of walk and don't walk and I'm not feeling well, I'm trying to get to hospital but I don't think I'll make it (he did by the way but not in his car).

Caller describes textbook symptoms of heart attack. and goes on "It can't be my heart I'm only 27"..

I talked him (And EMS cardiac care unit) into the same parking lot where he secured his car and transferred to EMS which got him to the hospital in time.

Yup, that was my phone number we are talking about.

[YC_1]

Since I have worked in the telecommunications industry for 35 years, own a service center that maintains 6 911 centers, there is always something one can learn. It is important to keep the information on emergency equipment as accurate as possible for the safety of all. You have done an excellent job of clarifying the issues.

[SCVJeff]

YC 1 wrote:

dave54 wrote:

YC 1 wrote:
Repeaters for police and fire will not pick up cell phone signals. If you are meaning their actual communications channels.

They use different frequencies and modulation techniques.

A separate antenna connected to different base unit on the same tower will receive 911 calls. Not too common yet, but increasing in mountainous rural areas.

Can you explain this a bit more please. Some new piece of communications equipment on the market?

Cell phones do not connect to 911 dispatch centers via their towers or radios. They connect via phone lines. The cell towers and vendors send that information via their infrastructure.

im interested as well because these are two completely unique and unrelated technologies.... And to that end, even the cell carriers frequencies and modulation techniques are completely different. It's simply impractical to pack all that into a cabinet and interface it to a conventional law enforcement "repeater" system, and then expect a dispatcher to understand what they even have. AND it would be illegal on many different fronts as well. So if there is documentation backing this up, I would like to read on how it's functionally done and the legal waivers to allow it..

As far as getting a usable signal on a non-registered cellphone, often those are not 'S' Meters, they are QOS, that looks at the signal as well as the loading on the system. Something I discovered with Nextel that would apportion the call coverage over two way comms with completely different readings into the exact same cell site.

[deleted-2]

Good to know info snowdance!

Interesting...thanx for posting.

[CentralCoastCam]

There are a lot of variables involved, such as different carriers use different technology. The carriers hand off the 911 calls to the 911 provider for that county, who route it to the appropriate call center, though with cellular, especially old cellular, that is guess work at its best. I would not rely on having an old cell phone as my primary form of communication in an emergency. Depending on its age and software, it might only transmit the lat/long of the cell tower ( phase 1 wireless) instead of the approx. lat/long of those phone (phase 2 wireless).. Of course, i still have a landline home phone for that very same reason. I have been a manager of a primary 911 center ( technically a Public Safety Answering Point or PSAP) for many years. In our quarterly meetings with our 911 providers (Verizon an AT&T ), there has been no mention of new technology as you mentioned, nor have I read anything about it in the NENA or APCO notices. The NexGen 911 will have more enhanced features, such as the ability to text 911. Texting is much more reliable than voice when there is sketchy service. NextGen isn't mandated in Calif until July 2014.