Next Week’s Bay Area Meetups

Next week we’ll be at a few awesome hardware meetups around the Bay Area, and we want you to head out and join us.

The first meetup will be the Silicon Valley Hardware Meetup at the Evil Mad Scientist shop in Sunnyvale. It’s going down Wednesday, December 6th, from 6:30 until 9:30. At least some of the Hackaday/Tindie/Supplyframe crew will be there, and the night will be filled with lightning talks, demos, and the cool hardware people you know and love.

Speakers for this meetup will include [Mitch Altman], hacker extraordinaire and owner of far, far too many TV remotes. He’ll be talking about hardware successes and failures in his own businesses. Also headlining the event will be [Clarissa Redwine] from Kickstarter. She’ll be talking about crowdfunding hardware, and the fact that making a thousand of something is a million times harder than making one of something.

The day after, on December 7th, we’re also going to be opening the doors at the San Francisco Supplyframe office to host the Hardware Developers Didactic Galactic. These Didactics are fun and popular, and you don’t need to go to the South Bay. Food and drink will be served, and there’s a sweet Rick and Morty mural in the alley across the street.

On deck for this month’s Didactic is [Tiffany Tseng], lead UX designer at Autodesk. Her work involves creating and implementing the design decisions that go into Eagle CAD. If you’re wondering why the icons changed a few years ago, she is not the person to talk to; that happened before the Autodesk mothership bought Eagle. If you’re wondering how the awesome push and shove routing actually works, [Tiffany] is the person to talk to.

Also at the Didactic will be [Asaad Kaadan]. He’s a robotics engineer working on cinematic tools for his day job and is currently exploring a very, very cool modular electronics project called Hexabitz. He’ll be talking about Hexabitz and designing for modular electronics.

Capacitors are Simple, Right?

It is easy to dismiss passive components like resistors and capacitors as a boring subject. [James Lewis] of KEMET Capacitors would disagree. He gave a talk about capacitor tech that is both approachable and in-depth.

Like every other component we use, we always think of them as perfect. But just like wires have resistance and inductance that we often ignore, capacitors have different imperfect characteristics that you need to be aware of.

Ceramic capacitors, for example, lose capacitance over time. Different ceramic material have different temperature sensitivity. Aluminum capacitors don’t last forever. Voltage applied to a capacitor can change its value as much as 50%.

[James] also talks about polymer electrolytics and super capacitors. His burning question: Is there any truth to the old guideline that you should derate capacitors by 50%? Want to know what he thinks? Watch the video below. Speaking of burning, he tackles the touchy subject of tantalum capacitors. The image at the top is a test Kemet ran on their own parts at reverse polarity well beyond spec. All of them are blown but only some look burnt. That’s a mystery well worth watching the talk.

Continue reading “Capacitors are Simple, Right?”

Hackaday Links: March 29, 2015

Every once in a while, the Hackaday Overlords have a Hardware Developers Didactic Galactic in San Francisco. Last week was #06 featuring [Mike Estee] from Othermill and Hackaday writer [Joshua Vasquez] talking about synthesizing an SPI slave in an FPGA. Video here.

It’s no secret that [Fran] is building a DSKY – the part of the Apollo guidance computer that was on-screen in Apollo 13. It’s time for a project update, and here’s where she stands: if anyone has a source of JAN-spec Teledyne 420 or 422-series magnetic latching relays (they’re in a TO-5 package), contact [Fran]. The backplane connector has been identified; it’s a Teradyne I/O 100 series connector with a 120mil spacing. Contact [Fran] if you know where to get them.

Let’s say you want a carbon fiber quadcopter frame. What’s the most reasonable thing you can do? 3D print a CNC machine, obviously. That’s a 200mm FPV racer cut from 1mm and 3mm carbon fiber sheets, but the real story here is the CNC machine. It’s a PortalCyclone, and even the cable chains are 3D printed.

What does an AMOLED display look like up close? Pretty cool, actually. That’s 20x magnification, and it’s not a Bayer filter. Can anyone fill us in on the reason for that?

Laser cutters are tricky if you want to do grayscale or half tones. [oni305] made an Inkscape extension to generate better GCode for engraving with a laser cutter.

19″ racks have no dimensions that are actually 19″. Also 2x4s aren’t 2 inches by four inches. Somehow, a 2×4 server rack works.