Ondo88

Member Since: January 24, 2011

Country: Spain

  • News - November Caption Contest | about a year ago

    (read with old batman TV show Theme song http://www.youtube.com/watch?v=1qP-NglUeZU)

  • News - November Caption Contest | about a year ago

    Banananananana Bearman!!!!

  • Tutorial - DOOM on your Pi | about 2 years ago

    while I was trying to load glxgears, I get the error: “error while loading shared libraries: libGLEW.so.1.7: cannot open shared object file: No such file or directory”.

    I’ve been looking around, and I’ve realized I have the 1.8 version of the file in “usr/lib”. There’s a way to get the 1.7 version also installed or I must wait for some update on the glxgears test?

  • Tutorial - Better PCBs in Eagle | about 2 years ago

    I know the tutorial it’s kind of old by now, but anyway, I’ve some extra tips that might help someone.

    • Tenting: It’s not only about having a better silkscreen on the board, soldermask will also protect your precious vias from rust and aging. It’s almost mandatory on RF and analog precision circuits. Without them CuO (copper oxide) will form a thin layer over your vias and pads, ruining your impedance adaptations. Pads are protected in part by solder additives, but it’s not a bad idea to use proper spray isolators on harsh enviroments.

    • Some PCB software offer “tear” connections for pads and vias. http://dangerousprototypes.com/forum/download/file.php?id=6979&t=1 That is an example of what I’m talking. This reduces mechanical stress around the via connection, avoiding possible rupture of the traces. Again, it’s also useful for RF applications, as it makes a better Z matching (it behaves as a tamper used in micro-wave circuits). In PCB software without this kind of feature, you can made your own tear connections manually if you’re concerned about some of that issues.

    • It’s a good practice to place holes around the boards, joining top and bottom ground layers. That makes the board more similar to a Faraday cage, reducing greatly effects from EMI (Electro-magnetic Interference). I had a board with that kind of problems, nothing worked ok until I placed the holes, it worked like a charm since then. If you like to make beautiful boards as I do, you’ll probably place that holes equidistant on the perimeter, but to be truth, randomizing the distance between the holes makes a better isolation as no single frequency gets benefited form constructive interference.

    • Get to know what you’re building. Before getting serious about PCB design, you should learn what is everything you’re using on them. I’ve always said you can know if someone is a good PCB designer by asking him to give you FR4 permitivity, solder fusion temperature and the like (without checking wikipedia ;D). When you make electronic design sometimes you can forget about physics, so be sure you know them well.

    • Another common mistake is not taking account of thermal activity on the board. Make sure your temperature sensitive components (like oscillators, and almost any analog circuit) are far from your heat generating circuits (regulators and the like). If your board fits in a box, be sure to have cooling paths that keep the things ok. Remember that heat goes up! (so don’t put your sensitive devices on the top if you can avoid that).

    • Some chips may have two Vcc or GND pins one to each other. On SMD packages it’s tempting to just join them straight, avoid that if you’re using oven soldering (very likely on production). That will unbalance the thermal forces your chip may suffer, moving it from its original position, and possibly making it tombstone.

    • I’ve found very useful to place a couple of squares on silkscreen, with an E (Error) and a T (Tested) on the side of each one. That allows you to mark easily your boards with anything you may have at hand, from a pen to a screwdriver.

    • The last one is the more ethereal of the advises, “follow your ground paths”. Your signal propagates from your Vcc to your GND, mainly through the shortest path, if two signals share that ground path, they’ll interfere each other. Try to make that paths as short and trouble free as you can.

    and most important, Have fun with your PCBs :D

  • News - A Good Ol' Fashioned Capt… | about 2 years ago

    “I’m pretty sure I can build another right horn with some LEDs…”

  • News - Free Day 2012 Recap | about 2 years ago

    Also, as it didn’t last 24h, your chance to win was geographically affected.

  • News - Free Day 2012 is Under Wa… | about 2 years ago

    Uhh… Seriously, next time you want to test your servers, say it and we’ll al point the LOIC at them. it’s easier that way…

  • News - Free Day 2012 is Under Wa… | about 2 years ago

    next time just use a random on users ID… It’s not only less painful for us, all that stuff is an inmoral waste of resources (and time).

  • News - According to Pete | about 2 years ago

    Just an idea, prisms. Insted of buying 800 lasers, get a few and make them go into prisms. It will make them keep an angle relation between them, but I don’t really think you care about that :P

  • News - Your December Caption Con… | about 2 years ago

    “And I left Burger King because everyone was nuts…”

No public wish lists :(