El Cheapo Cell Phone GPS Tracker

[zipstrip]

I am curious why this is a limited used option as an alternative to an expensive custom solution? Most places where I fly, I get decent 3G or 4G(LTE) coverage to "phone home" a longitude and latitude. Granted, realtime telemetry is somewhat off the table, but for a basic "come and find me" solution, I am not sure why this is not used more often. Thoughts?

 

[zipstrip]

I did not realize following FCC reg prior to initially posting: ''Prohibition on airborne operation of cellular telephones.

Cellular telephones installed in or carried aboard airplanes, balloons or any other type of aircraft must not be operated while such aircraft are airborne (not touching the ground). When any aircraft leaves the ground, all cellular telephones on board that aircraft must be turned off. The following notice must be posted on or near each cellular telephone installed in any aircraft: ''The use of cellular telephones while this aircaft is airborne is prohibited by FCC rules, and the violation of this rule could result in suspension of service and/or a fine. The use of cellular telephones while this aircraft is on the ground is subject to FAA regulations.''

If after the complete flight (timer used to boot the phone), why is this not an option that is used more often?

 

[JordanT]

After realizing the following insightful and valuable FAA reg: ''Prohibition on airborne operation of cellular telephones.

Cellular telephones installed in or carried aboard airplanes, balloons or any other type of aircraft must not be operated while such aircraft are airborne (not touching the ground). When any aircraft leaves the ground, all cellular telephones on board that aircraft must be turned off. The following notice must be posted on or near each cellular telephone installed in any aircraft: ''The use of cellular telephones while this aircaft is airborne is prohibited by FCC rules, and the violation of this rule could result in suspension of service and/or a fine. The use of cellular telephones while this aircraft is on the ground is subject to FAA regulations.''

If after the complete flight (timer used to boot the phone), why is this not an option that is used more often?

Are you sure that isn't limited to passenger aircraft?

 

[bigredbee]

This topic comes up every now and then. Using cell phone based trackers in rockets, balloons, UAV's, etc. while they are in flight is a violation of FCC rules.

Greg

 

[Rocketbuilder]

Ah, but most cell phones have an option for the timer and/or alarm that turns the phone on to sound the timer/alarm. So, you could set this feature to turn the phone on after the rocket landed, and then use the GPS to find it. This would not be in violation of the FAA reg posted above, because the cell phone would be off the entire time that the rocket was airborne.

 

[troj]

Assuming you always fly somewhere with decent coverage, and you want to pay for service on that second phone.

Neither applies, for me.

You'd need to disable the radio in the phone, until it landed, then have it enable the radio, figure out where it is, then somehow transmit that data to you.

-Kevin

 

[troj]

Ah, but most cell phones have an option for the timer and/or alarm that turns the phone on to sound the timer/alarm. So, you could set this feature to turn the phone on after the rocket landed, and then use the GPS to find it. This would not be in violation of the FAA reg posted above, because the cell phone would be off the entire time that the rocket was airborne.

That's a feature to wake it up, not turn it on when it's powered off.

To meet the FAA regs, the phone (or at least the radio) has to be off.

-Kevin

 

[user 8716]

This topic comes up every now and then. Using cell phone based trackers in rockets, balloons, UAV's, etc. is a violation of FCC rules.

The rule actually stems from the CFRs. Title 47 PART 22 Subpart H 925 reads:

§ 22.925 Prohibition on airborne operation of cellular telephones.

Cellular telephones installed in or carried aboard airplanes, balloons or any other type of aircraft must not be operated while such aircraft are airborne (not touching the ground). When any aircraft leaves the ground, all cellular telephones on board that aircraft must be turned off. The following notice must be posted on or near each cellular telephone installed in any aircraft:

“The use of cellular telephones while this aircraft is airborne is prohibited by FCC rules, and the violation of this rule could result in suspension of service and/or a fine. The use of cellular telephones while this aircraft is on the ground is subject to FAA regulations.”

 

[Rocketbuilder]

That's a feature to wake it up, not turn it on when it's powered off.

To meet the FAA regs, the phone (or at least the radio) has to be off.

-Kevin

On the phone I've got, the "power alarm" option will turn it on even when it is totally powered off; it's rather like a laptop computer in that it uses a small reserve of battery to keep the clock running, etc., but when it is powered off it cannot send or receive any wireless transmissions. It doesn't get any more "off" until the battery runs out.

 

[JordanT]

Which is why you can use a cellular dog tracker, which operates in every way identical to a phone in a rocket, but not a "phone". I wonder if you could use a 4" tablet...is a pocket computer without the ability to use voice (ie with a data only SIM) a phone? The FCC doesn't charge a tax on data only like they do for phone, so they must have determined it not to be a phone.

 

[Derek]

I'd be willing to bet most of these pet trackers don't maintain a constant cell connection in order to extend the battery life. If the polling time is programmable, you could set it to something like 5 - 10 minutes and be fairly confident that the cell radio is off during the flight. Even if it turned on during the flight, they are probably only connected very a very short period of time.

Of course this means it might take a little longer to get a response back from the device when you ask for a position update.

 

[Sooner Boomer]

Has anyone seen this:
https://blog.makezine.com/2012/11/08/fly-an-iphone-on-a-rocket-and-collect-data/

 

[Derek]

I wonder if he put it in airplane mode before launch?

 

[zipstrip]

This is an interesting idea regarding the "data only" plan. Not sure if the FCC contemplated that during reg development. As a fall back though, it is easy enough to re-activate the data capability of the phone after a given amount of time after flight i.e. turnoff airplane mode after flight. In either event, it would not be necessary to completely shut down the phone prior to flight just as long as the cell radio has been deactivated. Also, depending on the senstively of the accelerometer sensor of the phone, you might be able to get some rudimentary telemetry readings for post-flight review.

Certain used smartphones have become very cheap. This would be very interesting to experiment with.

 

[JordanT]

This is an interesting idea regarding the "data only" plan. Not sure if the FCC contemplated that during reg development.

I would argue that the FCC never contemplated the possibility of equipping (relatively) low flying or short-duration unmanned rockets with cell phones because of their combination of computational power and low cost. The prohibition for most commercial airline flights is to prevent distraction of passengers, since it has been known for quite a while that aircraft are almost entirely immune to the transmissions and noise of handsets. The bigger problem is more of a software issue for the carriers, as the phones will have a reasonable radio view of multiple towers, which causes more effective traffic on the system than a phone with a radio view of only a couple of towers. There is a proposal at the moment to allow cell phone usage above 10k feet.

 

[WillMarchant]

https://spectrum.ieee.org/aerospace/aviation/unsafe-at-any-airspeed is an interesting article from 2004 from our own Jay Apt.

 

[BEAR]

Assuming you always fly somewhere with decent coverage, and you want to pay for service on that second phone.

Neither applies, for me.


-Kevin

IN regards to the paying of cell phone service on a second line, I have a cell phone GPS tracker that was given to me by a friend, who was using it to track his wife because he thought she was having an affair (she was). This device uses a T-mobile prepaid account. I only get charged for the minutes I use. When the account runs out of money, I recharge it. This makes it very economical. For my tracker, it is working when the battery is installed. Hook the battery power up through a timer on the rocket. Turn it on after the time limit for landing, and then track. At least that is what I am thinking, because it is only theory (pardon my ignorance) because I have not flown it yet, and before now, I had not considered the legality. Thanks for this forum. You may have saved my butt. (HIJACK ALERT MY APOLOGIES)If you want a really cheap smart phone, SAM's Club is going to be selling Samsung Galaxy IIIs for $0.98 on Black Friday morning with the activation of a 2 year account. (A little overkill for a rocket? LOL) I am on Verizon's family plan with unlimited call minutes, text minutes. It will cost me $10.00 to add the line(s) and my monthly bill does not go up. I may go get a couple of them. (I think I can track them with the Droid OS)

 

[Derek]

I don't think I'd want to stick my shiny new galaxy s3 in a rocket I may never see again, especially if it was my regular phone as well!

 

[BEAR]

Oh come on, where is the fun and excitement in that. There is no adventure in holding back. I think I can get up to 10 of them with my current plan, and at $0.98 each, $10 is a real bargain. I could do it a number of times until I run out of phones.:wink:

 

[Derek]

you sure that $.98 price isn't for new contracts only?

 

[Derek]

actually it is $.96 and does require a new 2 year agreement.

 

[BEAR]

Thanks Derek for jumping in. Yes a new 2 year commitment, but, in my case, that does not bother me because both of my current contracts were up in August, so I can do that.

 

[zipstrip]

I think I am going to give this a go. Here is my approach:
1) I have a used CDMA (Sprint Network) capable ZTE unlocked phone running 2.3.5 Gingerbread. It's currently collecting dust so I will not feel too bad if it ends up as patio pizza. I checked Sprint's network coverage where I launch, and it seems like this network is a decent option.
2) Activate it on a pay as you go plan. PlatinumTel uses the Sprint Network and they appear to have reasonable rates. Monthly minimum: $3.33 Data: $0.10 MB. There are other inexpensive providers too. Pick your poison.
3) Download and install a task scheduling tool like Phone Schedule or TaskBomb task scheduler. There are a number of these "smartphone job schedulers" available in Google Play for free or (or for a fee).
4) Download and install a GPS Tracking app like Wheres My Droid or Android Lost Free. Again, there are a number of these types of apps both for a fee and free.
5) Prior to launch, setup Wheres My Droid to send coordinates. Setup Phone Schedule to deactivate "airplane mode" at some pre-determined time after launch as to appropriately comply with the FCC reg.
6) Put phone in airplane mode, pack phone in rocket and launch.
7) Wait for the phone to deactivate "airplane mode" and look up rocket cell phone GPS data using primary smartphone.
8) Walk to rocket (hopefully).

 

[cerving]

I wonder up to what AGL you can get a cell signal. The towers have directional planar antennae, with a relatively low beamwidth, so I'm thinking that you're gonna lose the signal at a few thousand feet AGL. Real-time tracking may not work, but you should still be able to use it for location after it lands.

 

[Right Wing Wacko]

I wonder up to what AGL you can get a cell signal. The towers have directional planar antennae, with a relatively low beamwidth, so I'm thinking that you're gonna lose the signal at a few thousand feet AGL. Real-time tracking may not work, but you should still be able to use it for location after it lands.

Actually, ONE of the reasons (of many) that Cell Phone usage in planes is illegal is at the request of the cellular companies. From 40,000 feet the number of towers that the signal from a phone can reach is so high that it could at the time overwelm the capability of the phone network to filter out. I beleive that particular issue went away long ago when phones went from Analog to Digital, but this can show you how long a rule or law hangs around after it's no longer necessary.

 

[cerving]

I have my doubts that from 40,000' away inside a tin can you'd get anything at all, but I doubt that anyone has been able to try it.

Theoretically you can get over 20Km over flat terrain like we have at Lucerne Valley Dry Lake. In any case, it's unmanned so I'm thinking that it skirts the reg since it's not in an "aircraft" regulated by the FAA, any more than a model airplane would be. (Yes, the FAA regulates rocketry but it's the AIRSPACE they care about not the rockets themselves.)

Actually, ONE of the reasons (of many) that Cell Phone usage in planes is illegal is at the request of the cellular companies. From 40,000 feet the number of towers that the signal from a phone can reach is so high that it could at the time overwelm the capability of the phone network to filter out. I beleive that particular issue went away long ago when phones went from Analog to Digital, but this can show you how long a rule or law hangs around after it's no longer necessary.

 

[bigredbee]

It's the FCC that's doing the regulation, not the FAA. The FCC regs make no mention of "manned" vs. "unmanned". And as far as interpretation goes, feel free to make all of the arguments and conjectures that you want, but that's for the lawyers and jurys to decide.

 

[cerving]

I think it's one of those issues where both agencies have their say in it. Ideally they'd get together on stuff like this, but that seldom happens.

I don't think anyone wants to get into any legal trouble over a silly thing like this. Does this apply to tracking-only devices like pet collars? Any lawyer-rocketeers out there who can weigh in on this?

It's the FCC that's doing the regulation, not the FAA. The FCC regs make no mention of "manned" vs. "unmanned". And as far as interpretation goes, feel free to make all of the arguments and conjectures that you want, but that's for the lawyers and jurys to decide.

 

[Derek]

I did some searching, and it seems like private pilots use their cell phones while flying quite a bit. I haven't found someone posting that they got in trouble with fcc for doing so.

I'd say that given the altitudes most of us fly at and the extremely short duration of the flight, the fcc will never know or care.

look at it this way: a 1000' flight isn't any different than being at the top of a 100 story sky scraper. how many cell towers do you think your phone can reach at the top of the stratosphere in vegas? is there a sign telling you to shut your phone off while up there? There wasn't one when I was up there a few years ago.

 

[Sully]

I have my doubts that from 40,000' away inside a tin can you'd get anything at all, but I doubt that anyone has been able to try it.

If you mean trying to use a cell phone from a commercial jet, I've tried it. Or at least I've checked to see if I had a signal once I realized my phone or tablet had been left on. No signal. And the plane flew on without any apparent difficulty.

I think that putting a phone or similar device in a rocket is extremely unlikely to cause any problems for anyone or to attract the attention of the FAA or FCC. It would be nice to have clarification, if only to reassure RSOs.