New subject: R: Layer23 missing

30 Sep 2011

Hi Bogdan,

...
  I've used all types of phones and
different networks - same result. If I capture the uplink then every time after a 
 few seconds I get "segmentation fault". My guess is that in a
controlled environment it's going to work, but with a live one, where you have a 
 lot of arfcn (on a quick scan I get about 50 on my location) it's unlikely to work. 

well, the success could depends from many things:
- wich cable are you using: FTDI or CP2102;
- which phone you have tried: sometimes the jack on C1xx could be not so clean or used and
it could create problems of communication at high baudrates.
- the environment that you are using: public network, as i saw from my tests, is quite
horrible to make tests (eg. arfcn hopping).

Using a DP-L10 and modifying the AFC value, seems to work well on public netwroks, even
if, sometimes it get stuck: problem related with channel hopping/sync IIRC.

I used a Blackberry Test Field to disable EDGE and identify which ARFCN that doesn't
hop on GPRS: ( eg. this one is hopping, others may not [1] ) 

Obviously a private and controlled environment could give you the full percentage of
success.

Regards,
Luca

[1] http://tinyurl.com/gprs-hopping

R: Re: R: Layer23 missing