Penny Auction Hacking; Put On Your Statistician’s Hat

June 14, 2012 by Mike Szczys 11 Comments

Penny auctions are where you must pay a fee each time you bid. Certainly this alters the behavior of the bidders, but there doesn’t seem to be a lot of info about exactly how. In preparation for an analytics degree, [Jay] decided to study penny auctions and see if he can win a contest based on his findings. Now he’s not necessarily looking to make a living by gaming the auction system. But we were interested to see how he went about getting information, and what he has to say about the results.

Since there really isn’t a large body of data available, he scraped it himself. You’ll want to page through his posts on the topic, but basically he’s using Python on a fast machine. This is made quite a bit easier through the use of Selenium RC, but it also means he’s got a lot of instances of Firefox running to track multiple auctions. Scraped data is stored in CSV files, and posted to his front page daily.

From what he’s captured so far [Jay] suggests that time of day, type of auction, and several other factors dictate when you should bid to attain the best deals.

MITx 6.002x Wraps Up; Here’s A Review From One Of The Students

June 14, 2012 by Mike Szczys 28 Comments

[Jorge] just finished MITx 6.002x with the fine score of 99.1%. Congratulations! We just finished reading through this review of his experience (translate) with the 14-week class and it sounds like the program is extremely well executed. For those that don’t remember, this is an intro to circuits and electronics course offered at the Massachusetts Institute of Technology. Except 6.002x is free to all as an online course (but if you actually want a certificate a fee may be involved).

Above is one of the many screenshots which [Jorge] took of the student web interface. It looks great, and offers pretty much everything you need to complete the class. The textbook, which runs at least $65 for a paper copy, is available through the web interface as part of the course. The labs even include web demos you can use to simulate circuits and probe and measure the resulting signals and wave forms. If you have questions there is access to the teachers, but also a set of forums where you can work with other students.

Perhaps most interesting is [Jorge’s] assessment of the time you will spend working on the class. He thinks that if you’re already familiar with electronics the work can be complete in about one afternoon per week. Scheduling is flexible — tests are available for one week, but once you start taking one it must be completed in 24 hours.

He believes this will be offered again in the fall so keep a look out for registration to begin.

[Thanks Pan]

[Ladyada’s] Thoughts On Quick-turn And Small-run PCB Houses

June 13, 2012 by Mike Szczys 50 Comments

So you’ve mastered your PCB layout software, and it’s time to make the board. But if you don’t want to etch your own you’ve got to decided where to have it fabricated. There’s a slew of services out there, most of which you cannot afford, but the short list of those you can is still pretty long. We think this set of PCB fabrication house reviews will help you make your choice.

[Ladyada] — aka [Limor Fried] — knows what she’s talking about. She owns Adafruit Industries and has done the lion’s share of designing the many kits and items they sell. If you’re going to charge money for something it better work right, and that involves lots of prototypes. But even if you don’t need a quick turn-around or numerous testing boards the post is helpful as she also covers some of the batch producers we’re already familiar with. These include DorkBot PDX and BatchPCB to name a couple.

[via Reddit]

555 Business Card

June 8, 2012 by Brian Benchoff 34 Comments

After checking out a few beautiful business cards while working at his engineering co-op, [Cody] realized he would soon need his own. Instead of a card with subtle off-white coloring, a tasteful thickness to it, and even a watermark, [Cody] decided to make a 555 timer business card.

[Cody] started his business card project by going through a few design iterations while figuring out what he wanted his business card to do. There were a few designs not chosen – one with a microcontroller, a few with just LEDs, and some with no circuitry at all. After checking out a few project from the EEV blog 555 contest, [Cody] decided to go with a simple 555 timer circuit.

Being a business card, [Cody] kept the circuit very simple; it’s just a 555, phototransistor, and a few SMD LEDs. When a 9 Volt battery is placed on the contact points of the card, the 555 lights up the LEDs. When a laser is shone on the phototransistor, the LEDs start blinking. A very neat and sufficiently interactive circuit that is perfect for keeping component costs down.

After the break you can check out [Cody]’s business card in action.

Continue reading “555 Business Card” →

KMODDL: A Mechanism Maker’s Dream Site.

June 8, 2012 by Gerrit Coetzee 20 Comments

Computers are relatively new still, but we’ve had mechanics for a very long time. KMODDL keeps us from reinventing the wheel. It contains collections of mechanisms with descriptions, pictures, and even videos. We were working on a arbalest design not too long ago, and we were having trouble coming up with a clever ratchet design for one of the parts. We spent a few moments in KMODDL looking through the ratchet section of the Reuleaux collection, and soon after we had the basic building blocks of our design. Sure there are books you could buy that do a similar thing, but KMODDL is completely free, very in depth, and easier to search. Plus, with a useful tool like this you might not even have to take apart all your appliances anymore to see how they work. My first sewing machine might have lived a longer life had I seen this first. Anyone know of more resources like this?

An Appeal To Microsoft To Consider The Hackers

June 7, 2012 by Mike Szczys 105 Comments

[PT] is climbing up on his soapbox again to make an appeal to Microsoft. We think his editorial is well-aimed; appealing for better support for hobby electronics in Windows 8.

This is of course not strictly a hobby electronics feature request, but deals with how a lot of USB devices are treated by the upcoming operating system. Specifically the Communications Device Class, which is a protocol used by most hobby projects (and boards like the Arduino) that take advantage of the Universal Serial Bus. The way communications are handled by OSX and Linux makes this a snap, but not with Windows 7. [Phil] post specifics about how the former two operating systems handle these communications, and how Windows 8 could be tweaked to fall in line with them.

It means not installing drivers. Drivers…. for a USB device. Think about that for a while and then ask yourself which decade Windows 8 is being developed in. Thanks for pointing this out [PT]. We often get spoiled using a Linux box and don’t realize the hassles sometimes found on other systems.

Getting Your Stuff Built: How To Shop, Conduct Business, Stay Alive, And Eat Your Way Through Shenzhen

June 7, 2012 by Mike Szczys 29 Comments

This is [Bob Baddeley]. He’s an EE with an idea that started as a fun project until someone said “hey, that’s cool”. He started thinking about what it would take to launch it commercially and before he knew it he was involved in a startup accelerator to help him assemble what he needs to make his idea into a business. He spent several weeks in China learning about manufacturing and posted copiously about it.

We’ve seen other engineering trips to Asia, but [Bob’s] experience living there provides a different perspective than a quick trip would. He posted about the thing’s you’d expect, like touring a short-run prototyping facility. But he also talks about the rigors of being a pedestrian in a place where legged transport is marginalized by the gas and pedal powered vehicles that are crammed into every square-inch of the city. In the image above he’s walking on the highway (for some inexplicable reason; deathwish?).

He also got to do a lot of fun stuff. He met a ton of folks, like [Bunnie Huang], [Ian Lesnet], and the team over at Seeed Studios. He even took his protoype to the local Maker Faire. It’s a scoreboard which can be controlled from your smart phone. [Bob] tells us that he didn’t get much interest showing the face of the device as seen in that post. But when he turned it around to show off the point-to-point wire porn he was mobbed by interested hackers. Guts!