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Calgary, AB
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Garh. Just had a notification from Daniel that our power-filtration capacitors were installed in reversed positions, with the 6.3V cap on the unregulated side.   :o

We had initially spec'd 16V caps for both positions, but we couldn't source them at the time, so we put a 6.3V part on (what should have been) the regulated side. We're working on an interim solution, but until then, use only a 6V adapter for externally-powered Freeduino SBs!

What surprises me is that the ones I've been using here in the office have been happily eating up 12V for a few months with no visible problem. Mind you, the electrolytic is probably leaking power like crazy, but the fact that it hasn't started to bulge is a testament to the quality of the capacitor!

We'll have notification and replacement information on the website ASAP.
 
Regards,
Dave (the Freeduino SB guy, who's sucking it up right now!) :-[
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Huh.  I take it that the unregulated side is the one closest to the DC connector on the SB board?
That's NOT true of all the "freeduino" boards; the PCBs I did that are posted at freeduino.org, and are the basis of the nkc "freeduino" boards, have the 5V cap next to the connector.  (basically, both unreg and 5V are present on both sides of the area where the caps live, so it's pretty much a whim which goes where.)
If you build one from a bare board, pay attention to whichever actual design you're using!
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Huh.  I take it that the unregulated side is the one closest to the DC connector on the SB board?
That's NOT true of all the "freeduino" boards; the PCBs I did that are posted at freeduino.org, and are the basis of the nkc "freeduino" boards, have the 5V cap next to the connector.

Yeah, that was an assembly error on our part. The unregulated side is nearest the edge of the board.
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until then, use only a 6V adapter for externally-powered Freeduino SBs!

Hmm.  I notice that my freeduino SB has a 7805 regulator, which means it won't produce 5V out of the regulator with a 6V input. :-(

On the other hand, I also noticed that the holes provided for a higher power regulator ALSO provide a means of "fixing" the board for higher input voltages without too much trouble.
1) remove the low voltage cap from the position near the connector.  Try to do this without damaging the traces of the PCB (unlike my attempt.)  Note that it's OK to destroy the cap, cause it won't be useful.
2) install a new through-hole cap in the bottom two holes provided for the regulator, with the minus side up. (GND is the center pin of the three for the regulator.)  Anything from 47uF (standard arduino value) up, at whatever voltage you intended, should work fine.  The photo shows a 220uF 16V cap I happened to have.)

   
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I received the "fix" for the solarbotics (wrong voltage) capacitor issue this week.  This consists of a 330uF 16V Through-hole cap and a page of instructions.  The instructions are clear, amusing, and they work.  The cap fits in the spot like the board was designed to have it there; it's exactly the right size...
« Last Edit: August 28, 2008, 06:50:45 pm by westfw » Logged

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Yeah, that was an exciting 6 weeks getting this all sorted out! Looks like we've got it all under control - all Freeduino SB customers were contacted with repair/replace options.

NOW can I start building projects with them?  smiley
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