Am Mi 4. März 2009 schrieb Helge Hafting: > Joerg Reisenweber wrote: > > Am So 11. Januar 2009 schrieb Alexandre Ghisoli: > >> Le Sun, 11 Jan 2009 19:07:40 +0100, > >> Konstantin <chaosspaw...@gmx.net> a écrit : > >> > >>> Matthias Apitz schrieb: > >>>> Hello Christoph, > >>>> > >>>> Could you please also make an offer for the hardware buzz fix in DE: > >>>> http://people.openmoko.org/joerg/GSM_EMI_noise/big-C_rework_SOP_rc2.pdf > >>>> Would be great! > >>>> > >>>> Thx > >>>> > >>>> matthias (one of your happy GTA02 customers) > >>> I second this one - offering the hardware fix for the freerunner > >>> would be great :) > >>> > >>> Regards, > >>> Konstantin (One of your other happy GTA02 customers ;) ) > >> Yes, hardware fixes (rework) made by resellers would be great. > >> > >> By fixes, I mean : > >> > >> * GPS - SDIO fix (add a capacitor if I remember correctly) > > There's a sw-fix for that, which mostly "just works" > > > >> * Add a GSM IR resistor for deep sleep > > Huh? > > > >> * Change the led transistor power hungry stuff > > Guys, this has been fixed for *ALL* FR ever sold!!! > > > >> * fix the GSM buzz > > ok, agree here. > > > > If I ship the phone somewhere to have a technician fix the buzz, I > definitely want the "small capacitors on headset output" issue fixed too. > > The capacitor, combined with the resistance of earphones, form a > high-pass filter. > > The cutoff frequency is 1/(2*pi*R*C), where R is headphone resistance > and C is the size of the capacitor. The capacitor in the FR has been > reported as 1 microfarad. My headset is about 40 ohm, which gives a > cutoff frequency of about 4kHz. > > At 4kHz the sound is halved, and drops by 6db per octave below that. > Above, the sound is almost normal. Unfortunately, most of the sound we > hear is below 4kHz. > > A headset usually works down to about 20HZ. If I want the cutoff > frequency there, a 200 microfarad capacitor is needed. > > Is there a plan for such a fix as well? > > Helge Hafting
Hey, you copied my mail from ~1year ago ;-) /j
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