From the Nokia 3310 manual, Alarm section:
Haha, oh well, at least I am not alone in my delusion! 
I remember the alarm going off, and then still having to switch it on and put in the code and everything. The reason I remember is that I was surprised when a later phone did not do this.
But it must just be the crazed ramblings from a brain confused over these past 13 years…
I agree that your phone is probably asleep, not actually turned off. But let us know the model and we can verify.
Hmmmm. I am now feeling very insecure about my assertion.
Motorola Droid X 2 On Verizon.
It is not just Hollywood fiction that a cell phone that is asleep pings the towers and can be triangulated. Three towers several miles apart, and you will find someone.
I’ve designed and written software for cell phones for over a decade. Lots of misunderstandings in this thread - let me try to clear up a few things.
When a cell phone is powered down…as close to off as it gets with a battery inserted…it doesn’t talk to the network. It’s can’t be remotely activated. It can’t be tracked.
The phone is typically in an extremely low power state, with a few different means to bring it up. One of those is the power button. Another is an internal clock (just barely sipping current from the battery) signalling an alarm - this is how the alarm clock feature works. A third is a charger being attached.
Since the phone isn’t talking to (or listening to) a network, it can’t be remotely turned on by the network. It also isn’t listening to GPS, so it can’t remember where it is and transmit the information later.
Now, a phone could effectively be faking it by looking like it’s off, but still doing talking on the network. As noted above, you’d notice the battery drain.
One minor exception to all this is a phone that supports certain types of NFC. NFC can function without an external power source…but not in any way to usefully track the general public.
Also, there was a note above that SIM cards can’t be hot swapped. There’s no technical reason you can’t do this. I’m not familiar with every model on the market, but I suspect there are some that allow it now.
I’ll be happy to go into more detail if anyone has more questions.
I love it. Nothing like getting the straight dope !! Thank you for the answer.
The key part of this article is here:
Which also fits along with what **Digital **is saying:
I think this makes sense, that a custom app could be installed which will make the user believe that the phone is completely powered down, when it’s not.
It’s my understanding, courtesy of a “good” leak to the NYTimes–which of course may have false information–that the American-Israeli Stuxnet campaign against Iran (or a different simultaneous program whose name I can’t remember) turned on the video and recording devices of who knows how many devices, including all Bluetooth ones, so other device and mobile communications were also tapped.
Just mentioning.
Just another reason to leave the thing at home.
As for battery drain- it might be small.
You might or might not notice, it could be close to zero depending on usage.
If you really want to be sure, wrap it in aluminum foil after turning it off.
If you want to test this, set the alarm, then remove the battery. I’ll bet that the alarm won’t go off anymore. That will prove that “off” is really “standby”.
No, wrap your brain with foil. That’s the only sure way to avoid being tracked by the Martians. Little devils, they is.
As mentioned upthread, alarms can be set to wake up the device triggered off the clock. You can consider that standby, but I don’t think it really is.
That won’t help if they’re tracking your cell phone, now will it?
Tell me how the device will wake up with no power.
The alarm circuitry is extremely low power (think about how little power a digital watch takes). It can be running all the time, while everything else is off (including the radio transmitter and receiver).
Remove the battery, and it won’t wake up. But the fact that the device is triggered by a timer (which granted, is drawing some power but it’s low level) doesn’t mean it’s in standby mode in any meaningful manner. It’s not connecting to cell towers or broadcasting anything unless someone has hacked the phone.
I guess we need to define “standby.” To me, it implies a partially powered unit, able to perform minimal functions and wake up fully when necessary. Whether or not standby mode includes pinging towers, calculating locations or playing tiddlywinks depends on the design, and if you want to call it “sleep” or “hibernate” mode, it’s fine with me.
I believe “Carrier IQ”, spyware frequently installed by vendors on Android devices, was found to be violating Airplane Mode.
The FBI have been using “Roving bugs” for years. A phone that seems to be turned off is remotely activated in such a way that it seems to still be turned off and the microphone is used to spy.
From a simplistic perspective…you have a hardware standby mode, and a software standby mode.
In hardware standby, all you have is a very few circuits being powered, including a low resolution clock. The clock can allow a simple timer to run. When the time elapses, it triggers a wake up for the whole system, which then comes up and notifies the user.
In software standby, you can wake up and go to sleep as needed…you can stay camped on a network if you want, although it will take noticeable battery life. If you go into airplane mode and let your display timeout, you are in a low power software standby. If you press the power key until it shows the device turned off, you are in hardware standby.
*All of this is architecture dependent. And not quite true. But it’s close enough for this discussion.
You have to remember that phone are sophisticated HARDWARE + customization SOFTWARE. It can be programmed to do just about anything. Sending a signal is native to the device.
It’s like thinking that your webcam is not watching you because the LED light is off. Well surprise - it can easily be kept off while the webcam works. Or come on with a certain cue (think Xbox one). The software needed to reprogram you phone to turn it’s ‘OFF mode’ into a ‘listen and track’ or a ‘wake to ‘fake off’ on signal’ or ‘ping check in every 10 minutes’ is not that difficult to use. The low resolution timer would serve nicely. A phone who’s battery CANNOT be taken out? It’s almost to much to resist.
Does you cell phone transmit data when it is off? It does if it is programmed to do so. It does if the NSA wants it to.:smack: