DCT-3 recycling as walkie-talkie

[nok_recycling]

Anybody thinked to use old Nokia phones as an "profesional" talkie-walkie ?
All that is required is an new ... SW ( and a lot of work of course )

advantages:
- good HW with good RF part - power 2W
- graphic display, full keyboard
- cheap
...
- once is implemented to one phone model it is easy to work in all DCT-3 series...

some idea/steps:
- lock phones to one free channel, user selected...
- use some test cards that has disabled encription algorithms... or use custom algo for encription...
- trick the phone sw to work without net presence... to work full time to an single channel in reception/full mode...

I can give for this project: some doc, sw and phones to test for this project, ftp space, my experience ... only for developers team at the begining...

I will start this after 14 days ( if anybody is interested ) when I will return at work...now I'm in holiday
- first I will try to use netmonitor & service sw wintesla feature to see how/if is possible...

anybody interested ?

[iuli]

Of course,good idea

[digicroxx]

I'm very interest too; this was one of my projects....

But first of all there is a problem:
GSM phones transmits in a band (890-915 Mhz for GSM900) different from the band that can receive (935-960 Mhz). In the phone there are filters tuned on that bands, that means that two "standard" gsm phones cannot connect together but only to the BTS.
I think that WinTesla let you tune the filters in the phone; we should check as first step if it is possible to "tune" the filters both on (e.g.) 925 Mhz or to "swap" the Tx/Rx bands...

BR
digicroxx

[wumpus]

A very interesting idea, but you will have to reverse engineer not only the MCU but also the DSP to see how the Hagar/Cobba internally works. Wether it is possible to transmit in a way the receiver can cope with.

I think we first need to grasp the GSM functionality, then we can try to figure out how to use the transmitter/receiver for other purposes.

[kraze1984]

And u'll also need a state's permission for using a frequency band......

[clayer]

i`m interested too

[<M457>]

very interesting!

[Mircea Vasiliu]

If a phone can switch Tx and Rx frequencies it would be very nice :)
If this works you could even turn the phone into a base station - provided you got enough free space to place the needed DSP code...

Of course this means reversing the DSP code

Best regards,
Mircea

[wumpus]

Yup.. reversing DSP code
Who dares :-)

I gave up on it :-(
Well I could still help with the MCU<->DSP protocol, but reversing the DSP itself is too evil for me ..

[nok_recycling]

After I studied a little some doc about phone design I seen that some major HW modification are required on RF part for set the RX on same frecvency as TX and this will involve at the end special tools for tunning wich I don't have access.

unfortunately this will go in an to complex project wiht major HW and SW modification and I don't think will be realisable at the end...

any way thank you for you'r interest in this...

regards.

[<M457>]

d'ho! :( :(

[scharpy]

I have an old 3310/3315.. Can i use it as walkie-talkie ? :)

[wumpus]

Indeed.. it would be very hard. Just buying a walkie talkie would be a lot easier :-)

Reversing DCT3 is fun for those interested in GSM, but using a phone for something entirely GSM-unrelated is unfeasible.

[nok_recycling]

look like they anticipate something...
http://www.theinquirer.net/?article=12380

[man0n]

THe original article from nokia:

Industry leaders Ericsson, Motorola, Nokia and Siemens mobile announced on September 10, 2003 the completion of a jointly developed Push to talk over Cellular (PoC) specification based on the IP Multimedia Subsystem (IMS) as defined by 3GPP.

The companies have submitted the specification to the Open Mobile Alliance (OMA) standards body for review as a baseline to provide an access-independent and globally interoperable standard for PoC. Go to the Press Release >> (http://press.nokia.com/PR/200309/916980_5.html)

New Direct Always-On Voice Service for GSM/GPRS Networks


Push to talk over Cellular (PoC) introduces a new real-time direct one-to-one and one-to-many voice communication service in the cellular network. The principle of communication behind the service is simple - just push to talk. Thanks to the 'always-on'1) connection, calls can be started to both individuals and talk groups with just a push of a key. The call connection is almost instantaneous and the receiver doesn't have to answer the call.

Push to talk service users are typically engaged in some other activity than a telephone call, and they listen to the group traffic during their activity. A user can be contacted by the name, or he may occasionally want to say something to the group. Half-duplex traffic is ideal for such use cases. This simple, real-time direct communication serves the diverse needs of both business users and private consumers ranging from controlled team management to spontaneous sharing of experiences. Among the many benefits of this solution over conventional two-way radio systems are the attractive GSM phones and the simple and fast creation of talk groups and group calls.

Push to talk service is a genuine differentiated voice service, because it is not a substitute of any existing cellular services. It gives operators an opportunity to develop their voice service offering without changing conventional voice services.

The Push to talk service is an integral part of the IP Multimedia communication portfolio envisioned by Nokia, and a part of the service offering in IP Multimedia Subsystem (IMS). It is based on half-duplex Voice over IP (VoIP) technology over the 2nd generation GSM/GPRS network. Thanks to the IP technology, the Push to talk service uses cellular access and radio resources more efficiently than circuit-switched cellular services, reserving network resources only for the duration of talk spurts instead of for an entire call session.

Nokia believes that Push to talk service must be based on open standards to enable multivendor environment and interoperability between different terminals and services. Nokia has participated in an industry initiative together with Ericsson and Siemens on the Push to talk solution and the solution will be open to other manufacturers as well. This solution offers terminal manufacturers an opportunity to implement the Push to talk facility across GSM mobile phone categories, thus giving end-users more freedom to choose the products that best meet their communication needs.

The Push to talk solution was published in 3GSM World Congress 2003 in Cannes. Go to Press release >> (http://press.nokia.com/PR/200302/891823_5.html)

1) "Always-on" means that a subscriber has typically direct access to the service after the subscription to it without additional measures (such as dial-up) provided that cellular network supports the service, is available and is not overloaded.

[t-mobile1121]

they have it in the usa on a network that is called i den with sim cards it only works in the usa tho

[duron]

I think this ideea should be tryed, and the best way is to use one phone as a base station... U get to modifi HW in just one phone(if it is really necesary) ... then U can use standard phones as WT... and extended range, by placeing the BS in an high spot... maybe U can even make your own GSM network... :D... :D

[badjunk]

Seems like the "Push-to-Talk" solution proposed by Nokia won't be free, I guess cell network operators ain't happy when someone is talking free of charge!
But the idea of re-using RF part of the phone looks nice, I think it should be one of the long-term goals of the MADos project. Of course a lot of work has to be done; but the idea itself looks promising.
Moreover, the "walkie-talkie" solution could be extended, making it look alike current P2P networks like KaZaA, eDonkey and others. What I mean: the phone is constantly switched on, but you don't talk most of the time anyway. When your phone is in standby mode, it can function as a base station, retransmitting the signal to the recipient or another "base station" within the range. Given enough people with such "modded" phones, we can eventually create a peer-to-peer mobile network, where you can call (or send sms to) anyone absolutely for free! Of course, standby time would decrease, but what about the idea?

2Anyone: let's discuss this topic!

[gorgarath]

Moreover, the "walkie-talkie" solution could be extended, making it look alike current P2P networks like KaZaA, eDonkey and others. What I mean: the phone is constantly switched on, but you don't talk most of the time anyway. When your phone is in standby mode, it can function as a base station, retransmitting the signal to the recipient or another "base station" within the range. Given enough people with such "modded" phones, we can eventually create a peer-to-peer mobile network, where you can call (or send sms to) anyone absolutely for free! Of course, standby time would decrease, but what about the idea?

Standby time would decrease, but how many people have an old spare phone sitting around that could be just sit on a charger all the time? I have like 2 old motorola's (pretty beat-up, but still work somewhat) and a samsung that I'm not sure if I still want to use or not. You could even modify the antenna to hook it up to an antenna on your roof, or house wiring or anything else to give it better range.

Even still, if you don't have an old spare phone, you can get one off eBay that works for pretty cheap if it's an older model that no one really wants anymore and mod it.

-Gorgarath

[fuzion]

Moreover, the "walkie-talkie" solution could be extended, making it look alike current P2P networks like KaZaA, eDonkey and others. What I mean: the phone is constantly switched on, but you don't talk most of the time anyway. When your phone is in standby mode, it can function as a base station, retransmitting the signal to the recipient or another "base station" within the range. Given enough people with such "modded" phones, we can eventually create a peer-to-peer mobile network, where you can call (or send sms to) anyone absolutely for free! Of course, standby time would decrease, but what about the idea?

2Anyone: let's discuss this topic!

i like this idea

[gorgarath]

Heh, apparently this has peeked the intrest of some of the moderators as well as it is now a sticky. I'll be the first to admit that I have no idea how it can be done, but given some guidlines or stuff to try, I'll try it. I'm all for it.

Sincerely,
Gorgarath

[kr00ki3]

Hmmm... and maybe MaDOS not reverse engineering ?? what do u think about it ?

[gsmsolutionsltd]

possibilites...............................................................

I will support.

[ramper]

Indeed.. it would be very hard. Just buying a walkie talkie would be a lot easier :-)

Reversing DCT3 is fun for those interested in GSM, but using a phone for something entirely GSM-unrelated is unfeasible.



Good idea wish i thought of dat. Although i can steal ur idea. I AM ONLY JOKING.

[eclectro]

By time you are done, you will have built a new phone. Hate to be a spoil sport.

I have to agree, purchasing a walkie talkie is much better for that purpose.

Also, the frequencies you would need to transmit on are strictly regulated by the FCC. If you are crossing the TX and RX channels to talk with each other, you _will_ be interfering with non-walkie talkie phones in your area. Also, you would have a hard time (read impossible) to talk with non-modded phones.

But if you insist, the best way is building a base station to do it, and modify your own phone sw to do it. In which case you have your own cell site, and might gum up the real one down the street.

I'm pretty sure the providers have ways to track down extraneous interfering signal sources, after all they have spent _millions_ on their networks and want to protect it.

Neat idea, but not really feasible for technical reasons.

It might be worth a try if there weren't commercially available units (at walmart) that are engineered extremely well and so cheap. In other words, there really isn't much novelty in it anyway.

The question you have to ask yourself is how you want to spend your time - do you want to do something that is available everywhere anyway, or do something _really neat_.

[gsmsolutionsltd]

Its about experementation,,,,what we learn along the way that counts................... :)

[eclectro]

Its about experementation,,,,what we learn along the way that counts................... :)

Sure, but if you're esperimenting you might as well try to do something that is viable and unique.

[florty]

Hey,i'am verry interested in this matter,and please tell me from where i can get the documentation about nokia HW and how to make software for nokia 3310,or,3410, :) ! Is there a compiler to do this?How to flash the nokia!Now i've made an mp3 player using pic microcontrolers and i want to combine pic tehnology with nokia tehnology! i'm already using a nokia 3310 display and i'ts verry simple!Please help!provide documentation!

[gsmsolutionsltd]

This will help get you started

click HERE (http://www.freewebs.com/gsminfo2/flashing.htm)

[florty]

10x a lot! But i can u tell me if there is an compiler to make the software ? Or there is one and it is in asembler!Is there one in c or c++?Probably not :( .Excuse pls my bad englis. :)

[ramcis]

to switch the filter to work with another frequence, it is possible by using software ?

[suppawat]

very good idea

[ramcis]

very good idea

there is someone who know how to change filter's frequence using software.

[vallentb]

By the way, I would like to use my old DCT3 phone as a GSM Jammer... That would be also great..

[ramcis]

Hi everybody,

Anyone know where can i find the info about the DSP used in 3310, and if there some routine was duilt for it.

We need to progress to perform this project.
Good luck for us :)

[tudor]

It's a TMS 54x 16bit DSP. You can get from Motorola a big datasheet. You can look in MadOS sources for some more info. I can't help you more right now, sorry.

[seaspac]

Hey,i'am verry interested in this matter------i want to combine pic tehnology with nokia tehnology! i'm already using a nokia 3310 display and i'ts verry simple!Please help!provide documentation!

Can you provide details how to use 3310 lcd ??

[seaspac]

Industry leaders Ericsson, Motorola, Nokia and Siemens mobile announced on September 10, 2003 the completion of a jointly developed Push to talk over Cellular (PoC) specification based on the IP Multimedia Subsystem (IMS) as defined by 3GPP.


It seems still push to talk operation involves Base Station? So no any 2 phones talking to each other but connected by Base station

[seaspac]

After I studied a little some doc about phone design I seen that some major HW modification are required on RF part for set the RX on same frecvency as TX and this will involve at the end special tools for tunning wich I don't have access.

unfortunately this will go in an to complex project wiht major HW and SW modification and I don't think will be realisable at the end...

any way thank you for you'r interest in this...

regards.

Actually its a very good idea to use transmitter and reciever of cell phone and certainly interesting enough to spend time on it.
It seems you are backing off due to complexity of the work, can you provide some thing about cell phone design so others can also study, understand and make some progress in this . I mean cell phone hardware and software working details and what is happening inside a cell phone.

Thanks

[demon_lite]

It is real with NokiX or need ARM programming?

[BlinK_]

It is not real with NokiX nor with ARM programming yet.