[Gta04-owner] Now that 3.2-final is out...

[Boudewijn]

On Sunday 08 January 2012 12:16:12 Dr. H. Nikolaus Schaller wrote:
> Am 08.01.2012 um 11:45 schrieb Neil Jerram:
> > NeilBrown <neilb at suse.de> writes:
> >> Also I started a wiki page to describe the current status in detail:
> >>   http://projects.goldelico.com/p/gta04-kernel/page/Mainline-Status/
> > 
> > This is really great.  I have a couple of questions.
> > 
> > Regarding suspend: what is the normal method for requesting a suspend?
> > 
> > Regarding the AUX and Power buttons: are they reported as KEY_PHONE and
> > KEY_POWER ? (as discussed in a thread about the hw-validation kernel
> > here:
> > http://lists.goldelico.com/pipermail/gta04-owner/2011-November/000678.ht
> > ml).
> > 
> > (I haven't built 3.2-final myself yet.  I did build 3.2-rc7+ a couple of
> > days ago, and it's working fine for me.)
> > 
> >> Also is there a simple way I can get a half-decent GSM antenna attached
> >> to the bare board?  With no antenna I get a signal strength of about
> >> '1' so I can see the carrier but that is about all.
> > 
> > Ah, that's interesting.  I am seeing low strength too, when running
> > QtMoko, but I thought it might just be a temporary thing.
> 
> Well, it can work, and indeed I recently forgot to connect an antenna
> while testing the 3G wakeup interrupts. And it simply did work, i.e.
> the module was registered to the network and did receive (and
> establish) an incoming call.
> 
> The GSM system is quite robust, but that said, it is very likely
> the GSM transmitter is blowing with full power to get some energy
> to the base station. This not only drains the battery very fast, but it
> also makes the UMTS module quite hot so that you risk it shuts
> down (there is some thermal protection).
> 
> Soldering a wire is not difficult, but removing it in a way that you
> can still connect a GTA02 antenna may be a little tricky.
> 
> And, it is very difficult to propose a wire length without doing
> some measurements with a very expensive equipment (RF network
> analyzer).
> 
> Finally, there is no single optimal length for all frequency ranges
> (850/900 MHz, 1800/1900 MHz, 2100 MHz).
As long as you're just trying one frequency at a time, an "about" correct 
length (even though suboptimal) seems to give good results according to a DIY 
GSM (900) antenna at [1]



> So I would recommend to take two plastic screws and mount an
> original GTA02 antenna (a plastic part + cut steel wires) to it.
> 
> Another option could be to use the test/car cit connector. The
> connector is a Murata MM8430-2600RA1 (DigiKey 490-1062-1-ND).
> 
> There are measurement probes converting to SMA
> (http://www.murata.com/products/catalog/pdf/k99/k99e_l0390.pdf)
> (DigiKey: 490-4982-ND) but besides the price, achieving mechanical
> stability without mounting into a Freerunner case does not appear
> to be trivial...



Wow... That's a lot for a piece of wire with connectors. I didn't find any 
offer for less than $50 in a couple of minutes searching. 



Does the antenna need coax or 2 poles? Or is a needle pinned in the connector 
sufficient to catch a (marginal) better reception? 



Boudewijn

PS: openmoko lists seem down?
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