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Observing my cellphone switch towers

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Re: Observing my cellphone switch towers

#111

Post by lizknope »

scrozier wrote: post #66
montroser wrote: post #55

Earlier quoted context omitted.

Yes, a similar thing used to happen to me just at this one particular bar in Chelsea. But it wasn't off by 19 years, it was off by just an hour, which is worse in a way. That made for some confusing drunken time warps until I figured out the pattern...

I was in a rental vacation house at the southeastern end of Lake Michigan three years ago. It was a pretty big house, and as you walked from one end to the other, the time zone would change. Really messed with me until I figured that out.

Antelope Canyon is a popular tourist attraction in Arizona.

During the summer Utah is on daylight savings time, Arizona does NOT observe daylight savings time but the Navajo Nation within Arizona DOES observe daylight savings time.

Antelope Canyon is on Navajo Nation land and requires a tour guide from a licensed tour guide company. The canyon and tour guides DO observe daylight savings time.

The canyon is only about 5 miles from the Utah border and many people are traveling from Utah. Because of all the competing cell phone towers you end up with people that show up at the wrong time.

I purposely brought an old school watch for my trip.

Re: Observing my cellphone switch towers

#113

Post by m463 »

lizknope wrote: post #111
scrozier wrote: post #66

Earlier quoted context omitted.

I was in a rental vacation house at the southeastern end of Lake Michigan three years ago. It was a pretty big house, and as you walked from one end to the other, the time zone would change. Really messed with me until I figured that out.

Antelope Canyon is a popular tourist attraction in Arizona. During the summer Utah is on daylight savings time, Arizona does NOT observe daylight savings time but the Navajo Nation within Arizona DOES observe daylight savings time. Antelope Canyon is on Navajo Nation land and requires a tour guide from a licensed tour guide company. The canyon and tour guides DO observe daylight savings time. The canyon is only about…

I recall in Nevada (Pacific time), there's one city right near the utah border that observes mountain time. I don't think my electronics figured it out.

edit: it is West Wendover NV

https://en.wikipedia.org/wiki/West_Wendover,_Nevada

Re: Observing my cellphone switch towers

#115

Post by lizknope »

m463 wrote: post #113
lizknope wrote: post #111

Earlier quoted context omitted.

Antelope Canyon is a popular tourist attraction in Arizona. During the summer Utah is on daylight savings time, Arizona does NOT observe daylight savings time but the Navajo Nation within Arizona DOES observe daylight savings time. Antelope Canyon is on Navajo Nation land and requires a tour guide from a licensed tour guide company. The canyon and tour guides DO observe daylight savings time. The canyon is only about…

I recall in Nevada (Pacific time), there's one city right near the utah border that observes mountain time. I don't think my electronics figured it out. edit: it is West Wendover NV https://en.wikipedia.org/wiki/West_Wendover,_Nevada

I've been there. It's a bunch of casinos literally a foot over the state border. It's less than 2 hours west of Salt Lake City. Wendover is a tiny town in Utah but West Wendover in Nevada is completely different just a foot over the border.

They probably want to stay on Mountain time because 99% of their visitors/customers are from Salt Lake City on mountain time and their TV stations are also probably from Salt Lake City

Re: Observing my cellphone switch towers

#116

Post by salawat »

VWWHFSfQ wrote: post #94
kmonsen wrote: post #92

Btw you do use this with stingrays to trick the phone into full power boost so it will use the battery very quickly. Useful if you want to encourage the user to go home to charge. I don’t remember the details but it has to do with selecting which cell tower is the best and how strong the cell phone needs to boost the signal are two different steps. Or at least used to be 10 years ago.

It seems that intentionally draining the targets battery would be counterproductive to the law enforcement's goals of tracking them

But not toward disbanding a protest coordinated by cell phone.

Re: Observing my cellphone switch towers

#117

Post by salawat »

coretx wrote: post #112

The jolly celltower adventure could ensue by indirectly reading the weather and even to forecast it. The least difficult aspect is measuring humidity. ^_^ Good luck!

Isn't any cell tower essentially a way to measure humidity as long as your receiver sensitivity and signal resolution high enough?

Given known EMI patterns along the path of propagation of course.

Re: Observing my cellphone switch towers

#118

Post by franga2000 »

grishka wrote: post #108
franga2000 wrote: post #52

Earlier quoted context omitted.

It's the same on Android - there's an "eco" mode of the location subsystem which will only use "passive" location indicators like WiFi and cell towers. In the "high accuracy" mode, GPS* will be activated, but until it lock onto enough satellites, passive location is used as a fallback/best guess.

Passive isn't that. My understanding is that it's piggybacking on other apps' location requests if there are any.

I might be wrong, but I think it's used for both. *EDIT:* I've looked around and I must've been misremembering - the term "passive" is only used in the official docs when talking about passive location updates (there called the passive "provider", since to the app, it looks like one). The non-GPS category of providers (wifi, bt, cell) is just called "network".

~~Passive location requests are, as you say, when an app wants location updates, but doesn't care when and how often - when one makes an active request, all the passive listeners get called.

Passive location sources are methods of getting your location with the data already available - so WiFi if it's on and cellular if the modem is on.~~

Re: Observing my cellphone switch towers

#119

Post by exikyut »

teeray wrote: post #79
Balantio wrote: post #3

How do i do this myself now? I always have put my phone in air plane mode when i was in a train due to the modem consuming a lot more energy. I always assumed and still doe its due switching towers and less connecitivy which means using more power. Whenever people argue that public transport doesn't need wifi i would argue against it due to power usage and also for more accessablity of the internet in general.

I think trains are kind of a special case in telephony when it comes to handoffs. It’s a unique situation where you have hundreds and hundreds of UEs[0] having to detach and re-attach, which makes for a very busy MME[1]. Sometimes those phones are only briefly connected to a given eNB[2] too, which makes all that effort for naught. [0] Phones [1] The system which sits immediately behind cell towers and coordinates ha…

The canonical solution in train/subway/metro systems seems to be full-length antennas that span the tunnel corridor.

The cool solution would be base stations built into train carriages that then uplink through some kind of backhaul.

I think (but need to properly evaluate) that some Australian trains use something like this. EDIT: Nooope nope nope, horribly misread. https://goughlui.com/2014/03/23/random-post-railcorp-gsm-r-r...

Re: Observing my cellphone switch towers

#120

Post by yuubi »

the8472 wrote: post #47
heelix wrote: post #45

Something like this would make it pretty easy to spot one of those stingray devices, I bet. Cell towers tend to stay put, so mapping out an area would go quick. Were a new 'tower' show up in an odd spot -- there may be shenanigans at hand.

the GPS location is reported by the tower, so nothing is stopping a mitm device from spoofing that too

In cdma2000, it's an option. I didn't notice such a thing in LTE. (LTE does include some options to determine position by propagation delay between mobile and base station, but they all involve the mobile reporting time measurements to the network, and then the network has the info to compute location).
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