Open... and close... and open...

Bokkertoff

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  1. 4GB RAM units freezing
  2. Really bad Wifi reception (which is what needs the measurements)
  3. Whirring noises when you connect something to USB or switch off the screen
Have the tests been done with the improved CPU board ?
I cant recall seeing any message that you produced any of the improved boards yet ?
 
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EvilDragon

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Have the tests been done with the improved CPU board ?
I cant recall seeing any message that you produced any of the improved boards yet ?
Nope :) But that would only affect the 4GB RAM, but as that's working now with the non-improved one already, it will also work with the final one.
 

Bokkertoff

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Nope :) But that would only affect the 4GB RAM, but as that's working now with the non-improved one already, it will also work with the final one.
Thanks for answering so quickly.
I would sleep much better :p if we tested the improved boards before production.
 

Bokkertoff

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ED's not crazy, the new board will be deeply tested before going to mass production
The CPU board has been improved as much as possible (thanks again to Juliano for the simulations!), so we're ready to start the production. As the circuit itself has not changed (we just added vias and a few capacitors), I am planning to order enough PCBs for the mass production already. A new prototype run is not really needed, as we now know we cannot further improve it and it should be good enough for 1,5GHz!
This would save us 6 weeks.
 

PCXT

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Wow, that's a very good news. There will be plenty of RAM in Pyra.

Whenever I'm at home, watching a movie with my wife or similar, I'm opening... and closing... and opening... the lid. Over and over again.
If it fails prematurely, it may be caused not by defective cable, but strains induced by closing and non-uniform twisting the cable back. I've seen it in some laptops. The test for this phenomenon is usually open, then close, then bang it slightly and observe/hear for any sounds from the cable. Sometimes there is a sound visible on analyzer right after the "bang", the coiled part of cable re-seats itself. The strain resulting from non-reseating cable may cause premature fail.
Such phenomenon happens in 200LX when hinges are subject to high abrasive wear. I know, there is a teflon-like washer there. My LX has typical markings of friction wear even on it. Just opening and closing few times a day since 1990s.
 

ible

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EvilDragon

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i thought someone made better wifi traces (juliano?), are those implemented in the current pcb, or are they yet to be tested on the next one? wouldn't the problem just go away then (hopefully) with the next pcb production run?
He made a calculation, yes, but it still differs a bit in real life and need to be fine-tweaked.
 

ible

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well the problems seemed a tricky to solve in the first post, but it seems like we're in very good shape. thanks for being so meticulous!
 

rv6502-2

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If there's any hardware expert here (or if you know one) who has some additional ideas how to locate the part: Please let me know :)
Get yourself an "Automotive Mechanic Stethoscope"

You lay down the end of the rod on parts without applying pressure to find where the noise comes from.

It's designed for finding higher frequency noise like rattling bearings.

you can tape or tie-wrap a smaller needle or pin to the stock tip if you need to.

Also, check capacitors. they are often the culprit.

 
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MrConfusion

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If there's any hardware expert here (or if you know one) who has some additional ideas how to locate the part: Please let me know :)
No expert, but a tinkerer. When building a project years and years ago I hit this issue and solved it by ducttaping (well, of course you got to have that :) a straw to my AKG C1000 condenser microphone (I screwed away the "decorating top"). I padded the straw slightly (cloth) so noise only entered via the end of the straw and the "root" (microphone end) was also padded with cloth. After that I simply turned all the audio knobs to "eleven" ;-). I then started moving the tip of the straw along the device to see where it sounded the loudest.

Worked for me, I found the problem. Two problems doing it though: 1. I nearly blew up my speaker when I told my dog to stay still and shut up (he ran away though, so very effective ;-). 2. I never got the ducttape marks away from my microphone...

... I wish the Internet had been a thing - the tips I've read here now sound easier and probably would have been sufficient to me ;-).
 

Grench

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The Prototypes - who received them and why?

I've seen that question somewhere on the boards, here's an answer for you.

First of, unlike planned, I have NOT contacted any of the Protoype orderers yet. Sorry for that.
There are two reasons for that: I first wanted to make sure that enough prototypes are there for devs and second: I simply didn't have the time to write the needed informations for the preorderers.
I hope to find some time for that during GamesCom. But right now, only mainboards with bad wifi reception are available - so that's something you'd need to cope with.
But, as promised when you ordered, I will send you a fixed mainboard once they're available in case you still want one of those prototypes.
Looking forward to the Prototype pre-order contact.

With regard to WiFi, I have WiFi USB adapters - so I could get by without fully working on-board WiFi for the mid-term.

However, if it's also making a racket (sirring?) when USB is being used - that could be a worse issue to try to work around. How loud is it? Is it a minor must be ear-on unit in a quiet room to hear or is it a wailing screeching makes the dog howl siren?

As far as the case goes, I'm good with clear, mixture of as much clear as possible and the 'dull' black of the other prototypes or even the dull black. I don't really need a fancy color case. If there are enough working clear and black case parts and CPU/Main/Display boards available to assemble a (mostly) functional US 4G LTE unit, I'm good with that. Especially if I can get updated versions of the boards (if needed) from future production batches.

The flip side, though, is that I'm last in line (#8) for Prototype Pre-orders and am completely in agreement of the "Devs first" methodology. So, I understand that I'll likely have to wait.

Thank you for the update!
 

elvissteinjr

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He made a calculation, yes, but it still differs a bit in real life and need to be fine-tweaked.
Out of curiosity, how would one go about fine-tweaking the wifi while avoiding another board revision? As far as I understand you'd need to have the new calculated wifi layout on the board to test properly, but the additional fixes are still gonna happen in hardware. Or is it just driver tweaking at that point?

On a second thought this might just mean it has to be tweaked to fit on the board layout... if that's the case, disregard my question.
 

EvilDragon

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Out of curiosity, how would one go about fine-tweaking the wifi while avoiding another board revision? As far as I understand you'd need to have the new calculated wifi layout on the board to test properly, but the additional fixes are still gonna happen in hardware. Or is it just driver tweaking at that point?
Reread the news post carefully: We'll make simplified PCBs for testing on confirming. PCBs that will only have everything for the Wifi reception on them.

What needs to be correct is the impedance and traces from the antenna to the Wifi-Chip. And the measurement equipment doesn't need any of the other components, just the traces and the antennas.

That will then be implemented into the mainboard PCB files which will then be produced.
 

Djoga'Ro

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@Zink's muffling idea one can work with. But instead off playdoh use foam.
Cover half your seach area with foam. If the sound got muffled, that half is your remaining search area. Otherwise, the other half is. Cover half your search area with foam. ... Binary search.
Should at least reduce the number of cadidates significantly.
 
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