Need help on a project

[steven_first_2001]

Hi all, I have had this idea of building my own cell phone from MOSTLY scrach. I know this probably sounds pointless and dumb but its just for fun and to see if it is posable for someone to do. It dosen't have to get any service or any thing, I just want it to have a cell phone that could work (If it was able to get service). I am good with electronics and all but where I fall short is in designing complex electronic schematics like the one I'm shure a cell phone would need. If any one can help out please do!! Thanks

 

[Nigel Goodwin]

Hi all, I have had this idea of building my own cell phone from MOSTLY scrach. I know this probably sounds pointless and dumb but its just for fun and to see if it is posable for someone to do. It dosen't have to get any service or any thing, I just want it to have a cell phone that could work (If it was able to get service). I am good with electronics and all but where I fall short is in designing complex electronic schematics like the one I'm shure a cell phone would need. If any one can help out please do!! Thanks

It's more than pointless, a cellphone is EXTREMELY complicated, it would cost MANY times the price of buying one (assuming you could even do it, or get the parts). You then have the problem of actually constructing it, the high frequency radio sections would be exremely critical to build, and you would need lots of very expensive equipment to do so. Then you have the actual problems of the physical construction, phones aren't made by humans, they are made by robot machines, I doubt you have the precision required.

 

[zachtheterrible]

It's more than pointless, a cellphone is EXTREMELY complicated, it would cost MANY times the price of buying one (assuming you could even do it, or get the parts). You then have the problem of actually constructing it, the high frequency radio sections would be exremely critical to build, and you would need lots of very expensive equipment to do so. Then you have the actual problems of the physical construction, phones aren't made by humans, they are made by robot machines, I doubt you have the precision required.

i second that.

a cell phone is WAAAAAAAAAAAAAAAAAAAAAAAAAY more complicated than you probably realize. have you ever tried crackin one open??[/quote]

 

[dingo]

hehe :lol:

Even if you were able to make it unless you spend heaps $$$$ for custom made chips. Using off the shelf standard parts it would be the size of a bar fridge.

 

[dak246]

Maybe you could make somthing more along the lines of a short range 2 way radio. You can possibly set it up so that the radio "rings" when it receives a transmission. Maybe you can make 3 or 4 of them, and set up a little phone number system where each receiver checks the transmitted number first, and if it matches its own, it will open up communications. You can add small LCD screens to them, keypads etc. Creativity is the only limit, but building an actual cell phone that would be functional on a real network is extrodinarily complicated as far as I understand, especially considering you would need knowledge of the encryption algorithms to actual use any data you would receive on a digital network.

 

[steven_first_2001]

I was well aware of the construction cost, but that part of the phone is not a concern. I am in a electronics school and any project I want is paid for by the school. You guys may be right about it being too hard though... but actuly I have looked at the inside of a cell phone and I did not think it was that bad. I guss I should mention that we have some nano-tech creation systems in our schools clean room so I am used to small complacated parts.

 

[JohnBrown]

The GSM protocol specification is about three feet high on A4 paper. I suggest you try something a bit simpler first, like sequencing the human genome.

 

[Nigel Goodwin]

I was well aware of the construction cost, but that part of the phone is not a concern. I am in a electronics school and any project I want is paid for by the school. You guys may be right about it being too hard though... but actuly I have looked at the inside of a cell phone and I did not think it was that bad. I guss I should mention that we have some nano-tech creation systems in our schools clean room so I am used to small complacated parts.

What other projects have you done?, it's best to learn to walk before you try to run! (never mind try to jump over the moon!).

I'm also dubious about cost not being a concern, I doubt the school have a blank cheque book for such projects.

 

[jrz126]

If you want a practical complex project, how about making an interface for a laptop LCD screens so that you could connect any device that has the stereo jacks to it, (like the output from a Playstation 2). This would require the same complexities (maybe alittle more), but it would have some use to it. You could even sell them, I'd be interested in buying one.

oh, and whereabouts are you in PA?

 

[Styx]

you are aware that mobile phones use ASIC's (application specific Integrated circuit) with newer ones using ARM RISC chips.

They are propiertory so no way of knowing the logic layout. Believe me this is way over your head and mine. 2 way radio is the best bet

Lets put it this way there are many parts to a mobile phone.
Digital
Analogue
Electro-mag

When I was at Uni the Nokia 3210 had just come out. One of our Dr was the one that designed the internal areal for it. He was made a Prof the next year, he recieved alot of money for developing it and he is one of the world leaders in electro-mag theory.

 

[steven_first_2001]

What other projects have you done?, it's best to learn to walk before you try to run! (never mind try to jump over the moon!).

I'm also dubious about cost not being a concern, I doubt the school have a blank cheque book for such projects.

I have bult many electronic projects, my best was I was able to use a basic 33Mhz cpu for a apple 2e. I am alowed to spend $5,000 for my projects this year and I wanted to build a cell phone just to do it. The complexity is why I want to build it. I don't know if were all on the same page though... by cell phone I just mean a phone that conects to a celular tower, it can take up a whole room if it has to. My teacher used to be a reverse-eginere a few years ago so he has some experince in this kind of thing he just never did a cell phone and would like to have at least a basic schematic to start off.

If you want a practical complex project, how about making an interface for a laptop LCD screens so that you could connect any device that has the stereo jacks to it, (like the output from a Playstation 2). This would require the same complexities (maybe alittle more), but it would have some use to it. You could even sell them, I'd be interested in buying one.

oh, and whereabouts are you in PA?

I live in somerset county.[/quote]

 

[zachtheterrible]

good luck

 

[dak246]

The problem isnt so much building it. Assuming right now that you already did build it you will need extensive knowledge of network protocols and how to implement them in your programming, and if you want to connect to a tower on a digital network you need to know the encryption algorithms. Now assuming you did manage to build it AND were able to obtain and implement all the code and protocols, you would probably be breaking the law since you in effect created a digital scanner of sorts that you would be able to use to listen to peoples phone conversations.

 

[steven_first_2001]

The problem isnt so much building it. Assuming right now that you already did build it you will need extensive knowledge of network protocols and how to implement them in your programming, and if you want to connect to a tower on a digital network you need to know the encryption algorithms. Now assuming you did manage to build it AND were able to obtain and implement all the code and protocols, you would probably be breaking the law since you in effect created a digital scanner of sorts that you would be able to use to listen to peoples phone conversations.

Well I don't want to break any laws in the process so maby I will have to give up just because of that. I don't think the building process would be that bad but the programming would be a bugger. If you lived around me you would quickly find that I have a apatite for knowlage and chalanges. I can be a complex person, and example is one of my fav. hobbies is studing quantum physics and building complex projects. I have a home-made turbine jet straped to a pedal bike that propells the bike to 110mph... What can I say? I'm strange

 

[dak246]

Thats not strange on these boards trust me. Ive build a CO2 laser and a pulse jet engine in my spare time. I wanted to make a turbine engine without using a turbo charger but with all that speed involved i couldnt find proper bearings. Im still just a newbie in electronics though. Anyway, Cell phones are just so hard to build because they are big business and incorporate so many industrial secrets etc....but im sure you could find some other type of project that would still be a challenge, yet still be doable.

 

[steven_first_2001]

Thats not strange on these boards trust me. Ive build a CO2 laser and a pulse jet engine in my spare time. I wanted to make a turbine engine without using a turbo charger but with all that speed involved i couldnt find proper bearings. Im still just a newbie in electronics though. Anyway, Cell phones are just so hard to build because they are big business and incorporate so many industrial secrets etc....but im sure you could find some other type of project that would still be a challenge, yet still be doable.

Glad to know I'm not the only crazy person here Hmmm a co2 laser, I want to build a laser but I don't want to do it unless it can burn things!!!! :twisted: What tipe should I go for? A later that burns things sounds like a good alternate to a cell phone don't you think?? :lol:

 

[dak246]

CO2 lasers produce a lot of wattage. My CO2 laser could easily burn right through paper...and could also burn a piece of wood if it was held at the right distance. The only real electronic thing you could do for it would be the power supply which is really simple, and maybe you could coordinate pressure, temperature and gas flow with with a microcontroller, but you would need to find the right sensors. Other than that its a physics project, but if you built a turbine engine it shouldnt be too difficult.

 

[steven_first_2001]

Well I'm not just in to electronics, I enjoy building other things too. In school I am alowed to do just about any thing I want, the only rules are (and they made these rules just for me ) It can't cause a explosion on a large scale, can't be used to harm anyone, and it can't be elegal. They let me build a stun gun and keep it in school for demonstrations. Any way, if you don't mind send me the specs on your laser. Maby we can make some plans and sell them on eBay! :lol:

 

[dak246]

Yea I can give you some specs on the one that I built...the only tools you should need are a drill press and electric saw, which I assume your school probably has. The materials should be easily attainable too. The only things you may have trouble with are the mirrors. For these you'll need gold plated mirrors, or copper or molybdenum discs, and even if you find them used they might cost over $100 each. If you search around on google you could find alot of info to get you started, but ill email you some design constraints and a list of what you need and some of the basic physics involved.

 

[steven_first_2001]

All right man sounds good to me. My email is steven_first_2001(at)yahoo.com (replace (at) with @. <----good way to keep spam bots from geting your email) Can't wait to get started! :twisted: