Bug #1024 (oscillating re-camping), a possible solution.

Nils Faerber nils.faerber at kernelconcepts.de
Wed Jun 10 16:14:17 CEST 2009

Werner Almesberger schrieb:
> Nils Faerber wrote:
>> For testing the process I tried to do the rework on a NEO1973 and
>> promptly got into trouble - I was not able to remove the capacitor! Is
>> it possible that it is glued to the board?
> Oh, so I wasn't the only one with that luck. When I tried to
> convince Dieter that replacing the capacitor was really easy,
> I decided to give it a swift try on one of the GTA01
> pre-production units I have and then brag about it.

The one I tried it on was a GTA01-V3.

> My first try was the "single iron, lots of solder" attack.
> To my great dismay, the cap didn't budge. I then went through
> all my electronics torture chamber has to offer, hot tweezers,
> etc., with pretty much the same lack of result. In the end, I
> reduced the problem to a simple mechanical one that could be
> solved with a dremel.

Uh - err... well... "torture chamber" ;)
I am quite hesitant to try that since I fear to hit other components in
the process - the crystal is pretty close, the other capacitor next to
it or even worse the Calypso itself. And then there are the fragments
flying around and probably getting stuck somewhere where they don't
belong - shiver...
On the other hand I also do not like the idea of having wrap wire in the
modem part - makes a good antenna for all kinds of interference.

Which Dremel tool did you use, the "disc/die" or the round Korund
(usually pink) thing? I think I will also try some SMD-Dremel-removel on
another already broken SMD PCB first ;)

> I didn't know the production models had glue as well. After
> the accelerometer and (probably) the backup battery, that was
> the only place where I've encountered glue so far. So it's
> probably best to avoid trying to remove the cap, and just add
> the new one in parallel.

Probably the glue was left from production models of the GTA02 or even

> - Werner
  nils faerber

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