To be more precise - the audio in G1 station can be accessed pretty easily - it's aLaw/uLaw in ISDN framing at 2.048 MHz. We have even built an emulator from some 74xx chips. However, such wide and fast logic analyzer would allow us to sniff DMA communication with one chip that looks suspicious regarding encryption - and it uses 6b address + 16b data + some control logic, totaling 33 pins and the internal clock is something like 16 MHz.

On 16.6.2017 01:11, P wrote:

The problem is RP-CELP specification for TETRAPOL is incomplete, even the bit order and meaning in voice frame is unknow. The goal is replace A/D converted in tetrapol radio which we posses and send well defined audio signals and sniff encoded audio on radio data bus. We already did this with analog signals using external audio input a got almost all bits solved, but few are still missing. This technique can be also helpfull to find out where radio does encryption and try to extract the encryption algorithm.

We have already some usefull setups and few more informations which are not yet published, but lacking required hardware and time to do this.

PJ

On Fri, Jun 9, 2017 at 9:21 , Алекс Тереж alextereg@gmail.com wrote:

...

Good day /Jiří Pinkav https://brmlab.cz/gitweb/?p=rp-celp.git;a=search;h=783b8c2e538d7fa7a6651df44ccf9010055b0ca9;s=Ji%C5%99%C3%AD+Pinkava;st=author,, /I wanted to know more about the 32-MHz signal analyzer for a 34 channel? Why, with such characteristics, maybe I have not yet fully understood your idea, what is its essence, maybe I will be able to help you something!

Best regrets, Alex White

2017-06-01 18:32 GMT+03:00 Алекс Тереж <alextereg@gmail.com mailto:alextereg@gmail.com>:

Ok, I anderstend you, wath can  help you and your comand  to create a working RP-CELP codec? And wath you meen said about  @t least 34
channels at 32 MHZ would be required to get the data out of bus) and this
seems to be blocker for now@. Do you have 2 tetrrapol radiostation, if yes can you sent to men voice trafic and record you voice talk of this station!

With best regards,
        AW

2017-06-01 18:15 GMT+03:00 Pinky <j-pi@seznam.cz <mailto:j-pi@seznam.cz>>:

    Hi,

    RP-CELP codec is not finished, a lot of stuff is still missing to reverse-
    ingeneer.  Implemented is only the first part of codec and even here are
    missing correct coefficients.

    We have some hardware but are missing digital signal analyzer (at least 34
    channels at 32 MHZ would be required to get the data out of bus) and this
    seems to be blocker for now.

    Thanks for interest, if You can imagine anny cooperation with this project,
    please let us now at tetrapol-kit@brmlab.cz <mailto:tetrapol-kit@brmlab.cz>

    With best regards,
            JP


    On Thursday, 1 June 2017 16.49.53 <tel:2017%2016.49.53> CEST Алекс Тереж wrote:
    > Good day *Jiří Pinkav*
    > <https://brmlab.cz/gitweb/?p=rp-celp.git;a=search;h=783b8c2e538d7fa7a6651df4 <https://brmlab.cz/gitweb/?p=rp-celp.git;a=search;h=783b8c2e538d7fa7a6651df4>
    > 4ccf9010055b0ca9;s=Ji%C5%99%C3%AD+Pinkava;st=author>, may name Alex White, i
    > want asked about use tetrapol-kit, namelly how to use and tersting  rp-celp
    > codec, is it work in uncrypted voice frame? At the moment, I'm good at
    > accepting, decoding and forming the output stream of frames in 120 bits,
    > but I can not test the possibility of correct speech processing by the
    > RPCELP codec even on unencrypted freem voices, because I do not have
    > TETRAPOL stations yet.
    >
    > Best regrets, Alex White

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