adding sim card reader to car stereo?

[pippen429]

hi everyone.

i am an apprentice electrician and have taken some basic electronics classes, but thats it so keep in mind when responding that i may not know what your talking about if it gets too in depth into the theory.

heres my question:

the car stereo that i have right now allows me to pair my cell phone with it via bluetooth, allowing me to talk through my stereo/car speakers. my goal is to be able to bypass the entire bluetooth operation and somehow wire a sim car reader out of an old cell phone directly into the stereo, allowing me to make phone calls without an actual cell phone being present. by doing this i wouldn't need to keep a charged cell phone in my car anymore because it would all be done within the stereo itself. keep in mind the stereo seen here: **broken link removed** already has the ability to dial the number directly on the faceplate, so all i would need is to implement the sim card.. i think.

i dont know how exactly these sim cards work (the one im working with is from t-mobile) or if it would be possible to make one from scratch. if anyone can lend a hand it would be greatly appreciated. diagrams/circuitry of similar or existing components are welcomed.

thank you.

 

[transistor495]

GPRS modems are there that accepts your simcard and communicate with pc through USB/parallel ports. Maybe you can replace the processing part with a uC unit and you go. See the image:

 

[pippen429]

im not sure what a uC unit is? how would i go about doing that?

 

[pippen429]

bump......

 

[cowana]

uC = microcontroller

 

[cowana]

Basically, there is no phone in the stereo - just the basics to connect to a phone., It is a really big job to add the phone part to it - more than just adding a sim card slot.

 

[Sceadwian]

pippens there is no way you could undertake a project of that scale with your current knowledge. This isn't basic electronics that's full blown complex system integration from nothing. The sim cards themselves are nothing more that stupid memory chips that contain the identification numbers that the cell phone needs to access the providers network.

I don't understand the purpose of your project though, you'll have to have a cell phone in the car to make the all no matter what, it'll either be a module like the one transistor linked which will have to be integrated with hardware and software into the car, and even then you'll still have to swap the sim card in and out, two cell phones can't be using the same sim card at the same time, the provider will disable the account, it's called cell cloning and it's very easy for the provider to detect, so you would need a seperate cell phoen in the first place. That being the case all you have to do is wire a car charge directly to the cars electrical system so that the cell phone charges whenever the car is turned on and put the cell phone and it's antenna someplace out of the way where it can still get signal, then you just leave the bluetooth on and you're all set.