Is it difficult to make a cell phone ( 4G ) ?

[Jan Audio]

Look i mean it all serious.

[MK14]

Look i mean it all serious.

Then the answer is YES, it IS difficult to make a (4G) cell phone. If you can't do surface mount components and/or can't even sort out buying a simple resistor, without accepting even the slightest/tiniest of compromises.

[Monkeh]

Nearly an hour now, 416 IPs and a total of 1.4MiB. Damn, I'm going to go bankrupt.

[JohnnyMalaria]

Perhaps OP should spend time reading articles like this:

https://www.techbout.com/stop-apps-using-cellular-data-android-phone-13411/

[ejeffrey]

You can also turn mobile data off on most phones.  I'm not sure if that impacts VoLTE because honestly I don't care, but it is a think you can do that will prevent it from contacting "10000 IP addresses per hour"

[james_s]

Look i mean it all serious.

Then the answer is YES, it IS difficult to make a (4G) cell phone. If you can't do surface mount components and/or can't even sort out buying a simple resistor, without accepting even the slightest/tiniest of compromises.

That's an understatement. It's difficult enough that I'm not aware of any hobbyist who has ever done it, and I've seen some really impressive hobby projects. It would be forging new ground, accomplishing something so complex that even well funded startup companies with teams of engineers have failed to complete a working prototype.

A much easier project would be take a basic off the shelf phone and write custom firmware for it to remove and lock out everything you don't want. You might even find a dozen other users out there who would want to use it, but most people are going to roll their eyes and wonder why.

[Alex Eisenhut]

Three transistors. No SMT. No Facebook.



IP connections over the last hour: 0

[MK14]

Three transistors. No SMT. No Facebook.

IP connections over the last hour: 0

Amazing, what you can do with ONLY 3 transistors.



Three transistor circuit, here:

https://flic.kr/p/akyUSv

[DrG]

Three transistors. No SMT. No Facebook.

/--/

IP connections over the last hour: 0

0 transistors, No SMT, No Farcebook, No Twatter, No Giggle, built-in speaker phone, No usage limits.


(you knew it was coming)

[Monkeh]

Three transistors. No SMT. No Facebook.

/--/

IP connections over the last hour: 0

0 transistors, No SMT, No Farcebook, No Twatter, No Giggle, built-in speaker phone, No usage limits.


(you knew it was coming)

But he can't find the right string! He only uses this one string he found 15 years ago at a car boot sale!

[tszaboo]

Three transistors. No SMT. No Facebook.

IP connections over the last hour: 0

Amazing, what you can do with ONLY 3 transistors.

It has these double wiggly things in them. Two of them. With lots of frequency probably. And a wiggly bit with an arrow.
Honestly, I rather have a small magic black box with lots of metal parts coming out of them, with the transistors inside, than the wiggly parts, because buying and selecting those is pain in the neck.

[MK14]

It has these double wiggly things in them. Two of them. With lots of frequency probably. And a wiggly bit with an arrow.
Honestly, I rather have a small magic black box with lots of metal parts coming out of them, with the transistors inside, than the wiggly parts, because buying and selecting those is pain in the neck.

It seems to be using a Quarts crystal, to very reliably/accurately set the transmission frequency, so a couple of adjustments, isn't too bad.

So, a crystal oscillator, using a speaker as a microphone, and the capability to transmit, all from just 3 transistors, which also can be reconfigured to act as the receiver, on the other side/unit. Seems quite cute/simplistic/elegant.

Who knows what other functionality, is contained within those magic black boxes (modern stuff). Does it/they send your private details to China/NSA/Hackers etc ?

[NiHaoMike]

Yes the network will block my working nokia dumb phone at 1 juni this year.
Those nokia telephones available now all have a camera, google assistent, facebook, all pre-installed.
I dont want those thing making use of my phone behind my back.

Did you know a regular used smartphone connects to 10.000 IP adresses within 1 hour ?
First of all i pay each month almost 7 euro, suppose that google or facebook becomes alive and uses the internet, i will be poor, they dont give a warning message if you need to pay above your normal payment,
they only send a message if i am to late with paying.

I dont believe you can remove facebook and google assistent from any phone, if it is possible show me please.
I always say : a smart-phone is for dumb-people.

Just find a phone that supports LineageOS.

[Jan Audio]

A much easier project would be take a basic off the shelf phone and write custom firmware for it to remove and lock out everything you don't want. You might even find a dozen other users out there who would want to use it, but most people are going to roll their eyes and wonder why.

That would be the best if that is possible.

Just find a phone that supports LineageOS.

Sounds linuxy/open sourcery.
That exists ?, nice one

[Monkeh]

It's just Android, so it's still a smart phone for dumb people.

[Jan Audio]

That's an understatement. It's difficult enough that I'm not aware of any hobbyist who has ever done it, and I've seen some really impressive hobby projects. It would be forging new ground, accomplishing something so complex that even well funded startup companies with teams of engineers have failed to complete a working prototype.

Imagine the freedom the world will have if this would be a normal DIY project.
Maybe someone will read this and have a nice plan.

[Bud]

Purism Librem phone

The Librem 5 is a phone built on PureOS, a fully free, ethical and open-source operating system that is not based on Android or iOS

[SiliconWizard]

After all those posts I'm not sure what you're really after.

As some of us said, you can buy some LTE module and design a basic cell phone (but still 4G) around this, some MCU, LCD display and a few buttons. Ready-to-use LTE modules are not exactly cheap, but there's really no alternative. Designing an LTE front-end directly yourself is a dead-end unless you're very experienced and have an enormous amount of cash to waste. So all in all, with a module, for about $100 of parts, and a number of hours of software coding, you could get there. I think there are already such projects out there that you could take a look at. If all you want is make and receive calls, that's doable. Now as I said, whether you'd actually be allowed to use this, I don't really know, but if you don't intend on selling it, it's for your personal use only, and you use the LTE module as documented, with a compatible antenna and clean power supplies, that should be OK.

Could be a fun project. But other than this, really I can't see why you wouldn't just buy a second-hand old mobile phone with no Android/iOS/Windows Mobile. Something just 2G for instance. I have no crystal ball of course, but I'm pretty sure those are still going to work on most networks for many years.

If you want something more modern, as I think others have already suggested, just select a phone that is supported by open-source initiatives, there are quite a few!
There are Android-based OSs with most nasty stuff either not included or disabled. There also are Linux-based OSs now. Those are safe bets for what seems to be what you want.

So here, you have 3 options. Make your own with a ready-to-use module. Or buy an old phone and use it until no network supports it. Or buy a newer phone and install an open-source OS on it.
Here a list of alternative OSs:
https://itsfoss.com/open-source-alternatives-android/

[tszaboo]

So here, you have 3 options. Make your own with a ready-to-use module. Or buy an old phone and use it until no network supports it. Or buy a newer phone and install an open-source OS on it.
Here a list of alternative OSs:
https://itsfoss.com/open-source-alternatives-android/

Or maybe we see next week a new topic.
"What temperature to use for silicon crucible?"
Hwy guys I'm trying to make a phone, and I decided that the best way of doing it is with custom silicon.
Now, I've seen the Escapist (great show) where Richard Hammond made glass in a crucible. I want to replicate this process but make 15nm transistors on it (I've hear that intel has trouble with their 7nm process, so I would only try twice as that). Also, what kind of microscopes do you use for this?

[Alex Eisenhut]

Germanium has a lower melting point. Probably easier to etch too.

[james_s]

Imagine the freedom the world will have if this would be a normal DIY project.
Maybe someone will read this and have a nice plan.

I have no interest whatsoever in building my own mobile phone. Smartphones are cheap and reasonably reliable, I don't use a lot of apps but the apps I do use are exceptionally useful. It is my phone, my camera, my music player, my GPS navigator and the remote for my home automation. My phone is a tool and one that I rely on heavily, I don't want to tinker with it and hack, I want it to just work. I wouldn't mind having a more open phone OS as an option but it would have to be quite polished for me to bother. Looking at what is selling well it seems the vast majority of people want big flagship phones with all the bells & whistles, I struggled to find a small phone but I've been pretty happy with the one I have.

[Mecanix]

Good read!

Time for Open Source Hardware/Software Mobility coupled with its own decentralized network me think. What's up with all the monopoly, restrictions and control? jeez... as if its all alien tech 11011001 or some intercontinental spying world annihilating device lol

Happy to donate to the upcoming crowdfunded network satellite launches too... hit it.

[Terry Bites]

Easy if you have a great engineering team, loads of cash and you can handle being sued by apple, google and other evil empires.
Not for doing anything wrong of course, but just because they can (ask AMD).
You might get your shoe in the door just before they cut off your head!
https://shop.fairphone.com/en/?ref=header  have been successful though, with a 70 strong team.

A real phone that just did calls and text would be a great leap forwards -burning batteries to run a load of BS apps is bad for the planet and our minds.

[Berni]

You can just buy a brand new "dumb phone" that connects to modern networks such as a Nokia 3310 3G:
https://www.gsmarena.com/nokia_3310_3g-8876.php

Or if you want it to be 4G there is something like this:
https://www.gsmchoice.com/en/catalogue/doro/7010/

There are dumb phones out there if you want one, you just have to look. They don't run any modern smartphone OS so they are not able to run any apps past the Java stuff that old phones ran, they don't have GPS, they can't open modern websites etc... One of the ways to find these phones is by looking for phones designed for elderly people, those are designed primarily for making phone calls since that's the only thing there target audience knows to do with them. You can rip out the camera if you don't want one(Those are mainly there for video calls).

But even if you have a 2G GSM phone the network operator will always know your location because the cell network uses that to work correctly(Handoff between towers and compensating for radio time of flight delay).

[2N3055]

But even if you have a 2G GSM phone the network operator will always know your location because the cell network uses that to work correctly(Handoff between towers and compensating for radio time of flight delay).

Some 10 years ago, I tested triangulation from towers, and could reliably get position down to 50m EPE with averaging....

It works so well, that smartphones use that to bootstrap GPS, even from coldstart of GPS, it will get position much faster ( 10 seconds ) than dedicated GPS device from coldstart.