Answer from Joerg (was: Re: Crackly Calls and Battery Tips! A5/A6 rework. Corrected URL)

Vasco Névoa vasco.nevoa at
Thu Dec 18 13:12:53 CET 2008

I did the big-c buzzing rework myself, with the precious help of a  
much more smd-experienced colleague.
It was very difficult to replace the resistor because of the proximity  
of the components around the mic. A very sharp soldering iron is  
I used a 1k resistor (didn't have a 2k2 of the same size at hand), and  
a 100uF/10V tantalum capacitor.
So far, so good! The buzz seems to be gone for good. :)
One caller has reported that I sounded like "at the bottom of a pit",  
but this can be the other older issue...

Citando Paul Fertser <fercerpav at>:

> Joel Newkirk <freerunner at> writes:
>> Still waiting for an answer from OM. (I posted a question in this thread
>> Friday regarding Tanatalum instead of Ceramic cap - the difference being
>> $0.25 vs $2 each in qty 100, and my radio guy thinks Tant is a good choice
>> for filtering, but waiting for word from Steve or Jeorg)
> Joel, Joerg overlooked your question on the community mailing list,
> you should have asked at hardware list instead. I asked him on IRC:
> here's the answer:
> 12:57 < PaulFertser> DocScrutinizer: could you please answer a
> question wrt capacitor type for the gsm buzz fix? Joel Newkirk asks
> whether he can use tantalum instead of ceramic ones as tantalum are
> much cheaper and he's going to perform a rework on a reasonable
> quantity of units (IIRC).
> 13:00 < DocScrutinizer> PaulFertser: we don't have any tantalum caps
> here, and I would guess they are just too big. I was about to suggest
> a free caeramic cap for everyone asking for it. actually I'll bring a
> handfull of those to Germany on Sunday
> 13:00 < DocScrutinizer> PaulFertser: technically there is nothing
> wrong with tantalum
> 13:01 < DocScrutinizer> though I'd guess they are somewhat harder to
> solder, as they're basically electrolytic caps and so won't stand much
> heat
> 13:01 < PaulFertser> DocScrutinizer: if you don't mind, i'm going to
> post your answer on the community mailing list in the corresponding
> thread.
> 13:02 < DocScrutinizer> go ahead, you're welcome
> 13:02 < DocScrutinizer> just quote this dialog is fine
> 13:04 < DocScrutinizer> also, to whom it may concern, I plan to join
> 25C3 congress in Berlin, and maybe rework a couple of devices there
> for free, or at very least give away caps
> --
> Be free, use free ( software!
> mailto:fercerpav at
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