On Wed, 4 Mar 2009 09:09:50 +0100 Joerg Reisenweber <[email protected]> (JR) wrote:
>Am Di 27. Januar 2009 schrieb Paul Fertser: >> >> Al Johnson <[email protected]> writes: >> > On Monday 26 January 2009, Christoph Siegenthaler wrote: >> >> are there any updates from resellers, FIC or any half-official >> >> DIY-tutorials on the hardware problems, i.e. the buzzing? >> > >> > This appears to have benefited from feedback regarding capacitor >> > types >from >> > the few people so far to have attempted the mod, >> >> The feedback is that: you can use any cap, including tantalum. :) >> >> > but more feedback is requested. The lack of feedback from people >> > trying it may be why it hasn't yet made it past release candidate >> > stage. >> >> No more feedback is really needed. Everyone who performed the rework >> confirmed that it eliminates the buzz. No single negative report. And >> i guess at least 10-20 people have already tried the rework. So, the >> reason that no reseller is doing it yet is probably due to >> communication/business issues rather than technical. > > >Exactly. >I'm not in charge any more to push this fix, but to me it seems we >really don't need to quantify "how much it improves" buzz-issue. >The cause and ways to creep in of buzz are well understood by now by >some guys at least (and NO it's NOT the mic catching RF near antenna, >it's pin4 of hs-jack), the bigC-rework is evidently (based on empiric >and EE basics) eliminating the ripple we see on MICBIAS, and a >gsmhandset.state file correctly using differential input mode >(control.63 value "Mic 2") won't break audio function from unfixed to >buzzfixed FR. Also we don't need any sophisticated test procedure, as >* all devices are prone to buzz issue, so we don't need to prove there >is buzz before fix >* the big-C rework will either kill the buzz or you find you did sth >wrong and mic stops to work. So any engineer doing the actual fix >doesn't need any sophisticated "fix succeeded" test more complicated >than that involved in replacing a lightbulb. Test call -> works -> >fine. > >cheers >jOERG > Hi, i am planning to do this on two units possibly (80%) this friday, i have one unit with and other without the buzz issue(*), both will undertake the fix. * the units were not used on same operator and in the same locations so i will try them first under the same conditions side by side to see if i can make my other unit buzz even if it didn't before. If this can be an opportunity for you to have me to test anything, please let me know. Petr _______________________________________________ Openmoko community mailing list [email protected] http://lists.openmoko.org/mailman/listinfo/community
