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<wolfspraul> Artyom (in absence) thanks a lot for detailing all your thoughts and decision making process!
<wolfspraul> that's very helpful to understand...
<wolfspraul> I didn't understand what judgment of mine you referred to though - did I say anything?
<wolfspraul> I planned to email the Qi list pointing to your great blog post, but haven't done that yet...
<wolfspraul> anyway, all good. thanks for the background info!
<wpwrak> whitequark: no idea. try and find out ;-) i wouldn't expect very visible damage. and it may be at a hidden layer. but you never know ...
<kristianpaul> !stats
<qi-bot> kristianpaul: 80923 words, 444998 letters, 10805 lines, 7.49 words/line, 251 actions, 2680 smilies, 1686 questions, 207 joins, 0 kicks, 0 modes, 0 nicks, 0 topics, time wasted: 1 year 2 weeks 3 hours 20 minutes , 50.53 idle-factor.
<kristianpaul> indeed, Reliaility !
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<Artyom> wolfsraul: I meant this statement: "wolfsprauldismissing arm is not smart and good imho". May be I just didn't understand the meaning correctly. But anyway I decided to explain why I had switched to MM SoC and put ARM away for some time.
<wolfspraul> ah
<wolfspraul> :-)
<wolfspraul> that was in NO WAY at all a reference to you
<wolfspraul> in fact you are very balanced and objective in comparing all this, which helps me (and others I think)
<wolfspraul> it's more a reminder to self to appreciate what ARM has done (and keeps doing), and take Milkymist to the next level, instead of trying to catch up
<wolfspraul> and of course, your findings may take you back to ARM, and why not?
<wolfspraul> we are passionate about making things work, I think
<wolfspraul> I would do that too, I want to get stuff to work...
<wolfspraul> meanwhile we improve Milkymist SoC, which will eventually be chosen because IT IS the best, not because it's a dogmatic choice
<Artyom> wolfspraul: I think we undertand each other fine now :) As I said I could misunderstand the true meaning of your statement ;)
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<whitequark> can anyone answer a relatively simple question?
<whitequark> DocScrutinizer: maybe you know?
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<DocScrutinizer51> whitequark: maybe I can answer, but only qhwn you pose the question here
<DocScrutinizer51> when*
<DocScrutinizer51> no way I'll open a webpage to rea it now, on mobile
<DocScrutinizer51> anyway the URL suggests you want to plug mic-in to errr line-out?
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<DocScrutinizer51> PLRASE KILL E!!
<DocScrutinizer51> ME
<DocScrutinizer51> or rather, kill billyboy gates
* DocScrutinizer51 can't stop headdesking
<DocScrutinizer51> c:\foo\bar\boo\CPU-A\conf\brd.cfg gets displayed in sourceinsight as brd.cfg[c:\foo\bar\...\conf\]
<DocScrutinizer51> BUT THERE'S ALSO CPU-B!!!
<DocScrutinizer51> guess what's display for cpu-b brs.cfg file in source-inight
* DocScrutinizer51 continues headdesking, while pondering suicide or 500kg TNT
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<DocScrutinizer> in explorer you got a decent full pathname in top addr textbox. Not so in "Open" and "Save as" dialogs :-(((
<DocScrutinizer> FSK wincrap!
<DocScrutinizer> +C
<DocScrutinizer> is there any tool to resize non-resizable dialogs, on windoze?
<DocScrutinizer> prolly not, and even if you could resize the "window" of that dialog, I'd bet the widgets inside won't resize accordingly - unless the unlikely luccky case the requester is coded in Qt
<whitequark> oh, was afk
<whitequark> DocScrutinizer: yeah, I have a GSM module with line-out and mic-in (electret)
<whitequark> actually, two modules
<DocScrutinizer> :nod:
<whitequark> and I want to plug the line-out of one to mic-in of another
<whitequark> should be pretty trivial, but I was unable to google it
<whitequark> bonus points for not letting TDMA noise to the line
<whitequark> both the line-out and mic-in are differential
<DocScrutinizer> use a R-divider to attenuate, with a 2kR across the mic lines and a 50..1000kR series to line, in series with a 100nF decoupling C
<DocScrutinizer> use a 1k load R across line-out
<DocScrutinizer> for the TDMA noise, you might or might not run into problems. Worst case you need a NF-transformer
<DocScrutinizer> but then, you as well can use some active circuitry, like e.g an optocoupler
<whitequark> ah. I thought that I could just use coaxial cables (I have a lot of these) for connecting the audio i/o to a shielded board
<DocScrutinizer> depending on particular line-out differential design, you might already have sufficient bias on one of the lines to GND, to drive the opto's LED with just a series R as external components
<whitequark> not sure if that would help actually
<DocScrutinizer> whitequark: regarding TDMA noise your main problem is common GND of both modules
<DocScrutinizer> the TX draws massive current bursts and thus introduces TDMA noise floor to its own GND level and in turn also to all inputs and outputs
<whitequark> my attempt at schematics: http://higgs.rghost.ru/36815621.image
<whitequark> have I got it right?
<DocScrutinizer> of course the differential input on the other module is meant to suppress those common mode noise components in signal
<DocScrutinizer> but that usually doesn't pan out
<DocScrutinizer> (right?) err, yup, just common GND missing at bottom
<DocScrutinizer> one line +
<whitequark> yes, about common gnd
<whitequark> with this scheme, I just connect LINE- to MIC-, right?
<whitequark> and they're not connected to the GND of the modules
<whitequark> thus they're not affected by noise floor
<DocScrutinizer> yes
<DocScrutinizer> but they are still affected by noise on TX module's GND as it will "lift" whole circuit's GND reference level
<DocScrutinizer> so both Line+ and Line- will have common mode noise
<whitequark> hm, yes, but how differential input won't reduce that to zero?
<DocScrutinizer> an ideal differential input will actually do that
<DocScrutinizer> problem is most of those "differential" inputs are not perfectly balanced
<whitequark> oh, the non-ideality of electronics ruining our clevermost plans...
<whitequark> if that would be the worst case, is an NF-transformer something like I could just go, buy and solder in?
<DocScrutinizer> ooh, and you want a 100nF in your GND connection as well
<DocScrutinizer> yup
<whitequark> cool, thanks. I'll buy the components tomorrow and assemble the device
<whitequark> ah, one more thing
<whitequark> the module has SMT antenna pads, so they recommend to lay out a PCB, then calculate a 50 Ohm trace and so on
<whitequark> I'm going to wire-wrap the entire device, so I want to buy a 50 Ohm antenna with a cable, cut its SMA connector off and just solder it directly to pads
<whitequark> would that work?
<DocScrutinizer> should
<whitequark> ok thanks again. I need to run now
<DocScrutinizer> if it's an unbalanced 50Ohm output, I.E. one of the two pads is GND
<DocScrutinizer> whitequark: you should calculate R2 so it attenuates your line-out level to sth like 100mV for 2k mic load R
<DocScrutinizer> err R1
<DocScrutinizer> for R1 you might reconsider 1k according to properties of your line-out. If that's e.g. no line-out but a dedicated speaker output, you may need a 100R rather than 1k, maybe even a 33R though I doubt the line-out amp is that picky
<DocScrutinizer> 1k is proper load for standard line-out as found on any arbitrary home audio equipment
<DocScrutinizer> standard line-out maybe 2Vss, so R1=50k
<DocScrutinizer> poti should be log type
<DocScrutinizer> with the spead end (the origin) towards mic-
<DocScrutinizer> spread
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<DocScrutinizer> whitequark: (trafo) http://www.conrad.de/ce/de/product/516201/
<whitequark> (antenna output) yes, it's unbalanced
<whitequark> (line-out) it can drive a speaker directly if it's not very powerful (a headphone), or they also have an example with additional amp
<whitequark> Load Resistance (typ) is 32 Ohm
<whitequark> and the diff. swing is 2.2V
<whitequark> *Vpp
<whitequark> as per the mic in, its working voltage is 1.5V, and diff. input voltage should be 740mV RMS to keep THD <5%@1kHz
<whitequark> at 0dB
<whitequark> and 15.9 mV rms at 20dB
<whitequark> I guess I should drive it with higher voltage, as the amp would add more noise at greater attenuation levels, right?
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