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Brundizzle B (verified by your mother)
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Real Life is Overrated
Real Life is Overrated

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+Yuji Naka +Michael Kukat 

Any suggestions for me?  I would like to make a bench power supply.
I have this transformer that transform 220V AC to about 10V AC.  with  rectifier bridge I make DC from it...    I use a 2200 uF capacitor to get a steady voltage.   the LED and resistor are just there to indicate it's on and to discharge the capacitor when it's off.   I then feed it into a voltage regulator (LM317T) to be able to fine tune the voltage.

I am actually thinking of connecting a couple voltage regulators in parallel (connection to point A en B) to provide me with 1V, 3V, 6V and 9V.    I also think I should build a current limiter in there. (maybe the easiest way would be a simple fuse) 

What I am still struggling with is the value of the smoothing capacitor.  2200uF seems to work...  but I am not sure if this is the best choice. I found a general formula for the value of a smoothing capacitor:  C = I * t / dV   (where t  time and dV is the voltage drop to be compensated by the capacitor.     In my case it is easy...  mains come at 50Hz and the 10V AC as well, so the gap between the peaks is 0.01 second.  Voltage drop seems to be around 12 V when I measure it...   However, I have no clue what the current is.  I tried to measure it using a crappy multimeter (used the 10A socket) and the meter read 19.5  ...  I suppose the thing would fuse over 10A ...  and it didnt.. so maybe it's 2A?   Also not sure if i measured it correctly..basically shortened it with the meter.

anyway...  any suggestions are welcome! :) 
 
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Who knows how to detach the black serial bus? (also the two smaller with the blue pieces?) Can i just pull them out, or am I supposed to lift/shift something? Thank you!
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+John Lewis I need your brain power for a sec... I think my chromebook (CB5-571-C506 / model:ZRF) has a keyboard issue... I'm actually sure.. the plus/equal key and volume keys are not responding :(

Both in ChromeOS AND Linux they don't work.. in both cases an external USB keyboard does work.

Based on this I think it's an actual hardware problem ... i.e. the key physically does not work (or the connection is broken somewhere)

the shitty thing is: the keyboard cannot be replaced (no screws... ) ... so I am thinking of getting a second hand replacement of the whole unit.. (see below)


Any thoughts?

http://www.ebay.com/itm/ACER-Chromebook-CB5-571-Series-15-6-Palmrest-Touchpad-Keyboard-EAZRF003010-a140/122667208316?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D46673%26meid%3D615d4601139141eea1c74bcb48081c49%26pid%3D100033%26rk%3D1%26rkt%3D7%26sd%3D122667208316&_trksid=p2045573.c100033.m2042

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found this "gem" in the Swiss Alps... anyone a clue as to what kind of crystal this is?
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woop woop \m/
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tgif... now what shall we do tomorrow?
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my thoughts and prayers are with the Swedish people and their "last Friday night"... keep strong.. we are there for you!

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