GSM-noise "buzz" issue

Ole Kliemann ole-om-lists-2008 at mail.plastictree.net
Thu Oct 30 16:43:07 CET 2008


Thanks for the answer!

The point is, i certainly won't do the fix myself. ;) I will send my
device to my distributor on warranty.

On Thu, Oct 30, 2008 at 12:11:47PM +0200, Joerg Reisenweber wrote:
> Seems you always could "upgrade" to the 'botch' fix found in A7 (It *should* 
> work, as our TPE engineers found it worth to implement in A7 ;-):

So as this fix is officially approved, I assume my distributor will
either be able to apply it or provide me with an A7. Gonna check with
them soon.

> > And - if you allow me to be off-topic - is there any improvement fix for
> > the headphone jack? I mean this hipass-filtering issue making music
> > sound quite tinny.
> a) place some decent 100uF (or as high cap as feasible) parallel to C4110 and 
> C4111. Make sure you don't create another contamination path for RF creeping 
> inside big can - maybe use a ferrite ring to block RF next hole where you 
> route some wires from those big caps inside can to C4110/11.
> b) *short* C4110 / C4111, and insert the 100uF somewhere else in audiopath, 
> b1)e.g. near R4405 / R4407 (you can even replace these R by 100uF 
> capacitors).
> You should remove R4117 and R4117 then, and instead place these 1k from 
> JK4401:pin2 and pin3 (! for JACK_INSERT function) to GND
> b2) or even place the 100uF outside FR in the housing of your hs-plug or 
> 2.5->3.5mm adapter

Is this somewhat official? Is it included in any newer revision? If not,
I don't think I can convice my distrubtor to do it on warranty. ;)

Ole
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