FC project direction

[Das Signal]

On Wed, May 27, 2015 at 04:21:43PM +0000, Spacefalcon the Outlaw wrote:

> OK, so you haven't been using the MS-147 connector on C1xx either yet?
> How were you connecting test phones to your USRP+OpenBTS setup then?
> Over the air?  Do you have a shielded room, or are both DL and UL
> transmissions of sufficiently low power that no radio regulators come
> knocking on your door?

The OpenBTS command-line interface has a power command. At 40dB attenuation,
the signal goes to zero after a couple meters (phone doesn't see the network
at all). So I believe even though I'm not in a cage, impact is minimal on
the surroudings. I also use GSM 850/1900 phones with a foreign MCC/MNC, this
way only my phone with the corresponding SIM card will try to authenticate.
The ARFCN (working frequency) I chose is completely unsused, too.

> It's just that every time I use a phone as a regular end user (Pirelli
> DP-L10 running its original proprietary fw since the spring of 2013,
> Motorola V66 prior to that, since 2003, seems to be a 2001 design), I
> constantly find myself cursing at various bugs and misfeatures in
> their UI design which I am powerless to fix because there is no source
> code.  These bugs and misfeatures won't go away on their own, hence
> I'm working on this project to build a Free Dumb Phone that won't suck
> - or at least the firmware for one.

Fully agreed!

> I suppose the specific UI misdesign issues I find myself cursing at
> wouldn't be there if I were a smartphone user, i.e., if I were to
> install QtMoko on my Freerunner and use it as an end user.  But then I
> wouldn't be able to share my joy with others - recommending that they
> also get a Freerunner would be pointless as these devices are no longer
> made and all unsold surplus is now exhausted - and the minimalist,
> all-about-efficiency engineer in me revolts at the idea of using a
> device with two processors and a full GNU/Linux OS to do a job that
> has been very successfully accomplished with single-processor devices
> using low-horsepower chips like Calypso running OSless or RTOS fw.

I like this minimalist approach too! And as you said, it gives more
control to the end-user, makes it easier to locate and fix bugs,
and in the long term helps to better our understanding of the GSM
protocol and how it's implemented in full.

--DS