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

[Dr. H. Nikolaus Schaller]

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.html).
> 
> (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).

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...

Nikolaus