Backyard Brains » Hardware

Now offering DIY “Bag of Parts” Kit for $49.99. Build your own Neuroscience.

Tim — Mon, 19 Jul 2010 16:07:30 +0000

Depending on what generation you are, you may fondly remember home-built AM radio kits. Backyard Brains is inspired by the amateur electronics heads of the 60’s and 70’s, and we now announce our SpikerBox “Bag of Parts” kit. You get the board, you get the chips, capacitors, and resistors, some instructions, and off you go! Here’s what it looks like when you are done.

And with the enclosure, which we also provide in the kit.

Here is a picture of our first customer who ordered the bag of parts version. Yes, Luis does have a MakerBot behind him. With such a 3D printer you can build your own enclosure. Unleash the output of your mind and hands, my fellow creatives!

How to Roll Your Own iPhone Data Recording Cable

Tim — Mon, 12 Jul 2010 20:37:59 +0000

Many users, while enjoying the SpikerBox demo’s we have done, have also expressed excited curiosity that the iPhone can be used as a portable data recorder / oscilloscope. To truly take advantage of your iPhone though, you want your signal to go directly to the line input. Though you can buy one of these cables, in the open-source spirit of Backyard Brains, here is the schematic to build your own. You need: one 4.7 kOhm resistor, one 10 uF capacitor, one 3.5 mm audio three conductor cable you cut in half, and one 3.5 mm audio four conductor cable you cut in half. Bring out your soldering iron, your wire-stripper, and your favorite beverage!

Wrap all exposed wire in electrical tape, cover with heat shrink tubing, and you’re ready to rock! This design splices the left and right audio channels in the microphone input, so if you use this cable to record music, you are only recording in mono.

This of course is our favorite use…

SpikerBox rejected by Computer History Museum

Tim — Mon, 12 Apr 2010 18:18:15 +0000

During Backyard Brains’ recent visit to California, one of our events was at the Computer History Museum. We are geeks at heart: Our heroes consist of the trilogy of Woz, Engelbart, and Roberts. Tim and Greg have gazed longingly at the core memory units, the signed Apple I, the memory drums, and all the other vintage artifacts in the wonderful museum. We dream of the day one of our inventions can have a place near the Altair and first Google Servers.

Thus, in a combination of humor and hubris (humbris?), Tim and Greg decided to donate their first SpikerBox board to the museum. We argued passionately to museum registrar Karen Kroslowitz that much as the computer revolution began with simple, homemade, and heartfelt electronics, we were attempting to do the same thing to the “neurorevolution,” and gee, wouldn’t the museum be honored to have our first board signed by us?

Sadly, wetware still is not in vogue at the museum, and we recently received our first board back. Ah well. They’ll come around.

Leaving the museum, Tim spied an old VW bus like his parents used to have in Germany in the 70’s. It’s not an El Camino but it will do. One day.

ByB Says thanks to “Stew” of RadioShack.

Tim — Fri, 22 Jan 2010 17:36:19 +0000

Though online retailers such as Mouser, Digikey, and Sparkfun have huge inventories and are cheaper, sometimes it’s just faster to drive over to RadioShack at Briarwood Mall and pick up a component. Plus, there’s the aesthetic appeal of holding parts in your hand, staring at them, and getting a sense of the final design. Many an idea we have had simply looking and daydreaming at the stock shelves.

ByB hereby gives a heartfelt thank you to “Stew” of our local Radio Shack, who has often helped us find just that part we were looking for. There’s still a place for gearheads past all the cell phone accessories…

First Recorded Spikes on the OLPC

Tim — Sat, 08 Aug 2009 20:46:05 +0000

While Greg and Evan have been working on modifying the Measure program on the OLPC (one laptop per child) in order to view and store neural data (the current build can’t store data, and it needs a trigger function and better visualization), Tim has been experimenting with the Audacity program. This is the same program we use on our PCs and Macs to view the neural data; the program is open source and has excellent signal processing capabilities (Tim has even written songs using this program).

Audacity is in its first OLPC build (you have to launch it from the terminal), but it works!

In the picture above, you can see the SpikerBox (with a cockroach leg on it) going to the microphone input of the OLPC, and Audacity displaying the neural data. The three bursts in the center of the display are when I blew on the barbs of the cockroach leg, causing an evoked discharge in the nerves. The software works well enough for demos, but there are three things we would like to see:

1) Fixing the play-through function during monitoring and recording. Listening to the output through the computer speakers while Audacity is recording is important for our teaching purposes. Turning on “Software Playthrough” causes Audacity to only record 1/2 second then crash.

2) Saving the recorded data in the journal of the OLPC. From the save menu of Audacity, you cannot navigate to the

/home/olpc/.,sugar/default/datastore/store

directory (which is the journal directory), as the .sugar folder is invisible in Audacity. Right now we are saving to the Audacity applications folder.

3) This is a minor thing, but wrapping the Audacity program so that it can be loaded from the main OLPC application page (rather than the terminal) would be nice.

Stayed tuned. We continue our labor of love…

Above is a screenshot from the OLPC. You can see the spontaneous discharge nicely (as well as when I blew on the leg on the right side of the display). Having received my chops in Mammalian Extracellular Neurophysiology, I am amazed at the signal to noise ratio of invertebrate neurons. Cockroaches have it going on!

Demo at Ripple

Tim — Sun, 26 Jul 2009 15:24:18 +0000

While Tim was on a roadtrip for an interview with the Kauffman foundation, he made a pit stop in Salt Lake City to visit some friends at Ripple. While we at Backyard Brains pride ourselves on our single channel neurophysiology, the engineers at Ripple are designing a >1000 channel neurophysiology system! We picked their brains (using language of course), and you can see Shane Guillory skeptically analyzing the output of our SpikerBox:

The folks at Ripple are enthusiastic about ByB, and kindly offered up some help on circuit design, publicity, and partnering at conferences. Look for us occasionally hanging out at the Ripple booth at SfN in Chicago. There may be some new implementations of Mind War…. Thanks for lunch guys!

SpikerBox v3 Prototype Complete!

Tim — Wed, 15 Jul 2009 16:23:25 +0000

You spoke; we listened. Version 3 of the SpikerBox is complete and fully operational. New features include: built-in Speaker, Gain Control, rapid switching between audio and recording mode, and three standard outputs: BNC, mini-stereo, and RCA. We have a couple more improvements (smaller size, smaller batteries, etc) to make, but stayed tuned. We foresee Version 4 being the market-ready version. Thanks for your patience everyone!

What did the previous versions look like? See SpikerBox1 and SpikerBox2.