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PolkaDot last won the day on May 29 2013

PolkaDot had the most liked content!

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  1. First etch & surface mount!

    http://www.kickstarter.com/projects/otherfab/the-othermill-custom-circuits-at-your-fingertips?ref=live This is one I saw; going for around $1300.
  2. Recently had my first go at printing a board and soldering surface-mount components. It's a straight-forward breakout for an FT230XS. Technique: On the etching side, I used a 2:1 mixture of Hydrogen Peroxide solution and Muratic Acid. Initially clear, it turned a lovely neon green when the copper started reacting! Etch took maybe 5-6 minutes. I used an "ultra fine tip" Sharpie as the resist; learned the hard way that the 'Micron' brand of super fine tip pens doesn't work for this application :-( . I was struggling to mark the pads with the sharpie, so instead I drew a dark box across an entire row of pins then used a type of dental pick to scratch a fine line between adjacent pads. Seemed to work pretty well! I had bought a syringe of solder paste for the occasion, but ultimately I couldn't make it cooperate--globs kept bridging pins. Eventually I just put down solder on all the pads, put some flux on the pins and reflowed that way. Anyhow, it was a somewhat messy learning experience, but hopefully next I'll print/mount the whole module. Will keep you posted!
  3. QFN/BGA assembly?

    So TI puts out a lot of awesome $2 chips, many of them QFN packaged (especially in the wireless world). But idly looking around, having a board with any number of lead-less packages assembled is super expensive! I mean >$10 per board at ~1000 volume. I understand it's because they X-ray the boards to evaluate the solder joints, and you can do it yourself with hot air, but it seems like there's a jump from maybe 100 (DIY) boards to 10,000 (mass produce) to maintain reasonable cost. Is there no way around that? It just seems odd to put out a bunch of dirt-cheap chips, but exclusively packaged in a way that costs 10x as much to assemble.
  4. Motorised Slider.

    Very cool! What's your total slide length?
  5. New Energia release 0101E0009 - 12/06/2012

    On loading blink I'm getting a "CreateProcess error=2, The system cannot find the file specified" I'm running Windows 7, 64 bit. Lay the knowledge on me
  6. I do want the CC3000 board.. but I think a friend is giving me one for free 8-)
  7. Useful chips

    I think this would be extremely useful; reference to some sample code or nuances learned the hard way, as I see in these threads, is invaluable.
  8. [Call for Designs] CC3000 WiFi BoosterPack

    Bumping this back up because it seems there are a few CC3000MODs scattered across a few distributors, and I'm hoping to rekindle some discussion on the Boosterpack/Energia libraries TI's boosterpack still isn't available, though I got my sample module a couple weeks back.. and I think I saw TI has the design files online. Perhaps we can print a few? Also just generally, what do the Murata and LSR modules actually add beyond the reference design? I'm just trying to figure out where the $40 price hike comes from.
  9. Picked up an o-scope at a pawn shop auction; $3 =]

    1. bluehash


      Haw! which one?

    2. PolkaDot


      It's an old Kikusui cos5030

  10. PCB Calculator Programs

    While we're here, can you recommend or link to any recommended software packages? Much appreciated
  11. Contest : Show off your Avatars

    I'm in; made this for the pcb logo thread, decided to make it my avatar, then saw this--perfect! It's a raccoon, because engineers like cute fuzzy things.
  12. 43oh PCB Logo

    Or a curious 'coon, because why not. https://www.dropbox.com/s/fam980m7xvn8xbs/43oh%20Racoon%20Polka.png
  13. 43oh PCB Logo

    Perhaps something that sleeps a lot.
  14. 43oh PCB Logo

    I was never a huge fan of images as text, myself. I feel like good graphics and good font should coexist. Or maybe 43oh needs a mascot ;-)
  15. 43oh PCB Logo

    Maybe try this guy on for size? https://www.dropbox.com/s/k1t9e04y6oxvkgl/43oh%20Polka.png Sorry for the link, but couldn't put it in the post. Also ignore that weird black stuff..