Our engineering department is working hard on the next generation of the SpikerBox. The chief user request we’ve received is to make the SpikerBox louder; in fact, loud enough for large classrooms. Below is the audio component of our circuit, using the infamous LM386. Making this audio component both loud AND stable has been a major challenge, but we like challenges at Backyard Brains.
We know we can put a 10 uF capacity across pins 1 and 8 to increase to 200 gain, but stability goes out the window. If any analog electronics engineers in the world know an alternative low-cost, low-power audio driver, or a stable LM386 arrangement, please let us know; the solution is near.
Another common user request is to have the ability to both use the iPhone/iPad and hear the spikes at the same time. At the moment, the iPhone OS doesn’t allow playthrough (please Apple, do this for us?), but below is a cheap hardware solution that also solves the loudness issue. Go to your friendly neighborhood RadioShack, and purchase:
1) A mini Audio Amplifier for $14.99: This portable audio speaker amp will allow your spikes to be loud enough for a large classroom or lecture hall. It needs a 9V battery.
2) A Y-adapter for $3.59 to split the output of the SpikerBox to two outputs, so that you can plug in both the iPhone/iPad and the loud audio speaker
3) a 1/8 audio cablefor $3.99 to go from the SpikerBox (or Y-splitter plugged into the SpikerBox) to the audio speaker.
Note: the Y-adapter and audio cables listed are the monaural versions. The Stereo Versions (cable and Y-splitter links here) will also work fine but are $1-3 more. We usually buy the stereo versions anyway, as they are useful for other audio projects. Here is the standard lab class set-up. The iPad works even better for lecture halls.
Note: our kind friends at RadioShack customer service actually sent us the circuit diagram for the audio amplifier! This scan is how we actually received it. Notice they have put a transistor in front of the LM386. We are experimenting with a similar arrangement. Stay tuned!
The annual Society for Neuroscience meeting is a big event for us; we prepare all year working on new prototypes and experiments for annual review by our colleagues, friends, and academic foes. This year was a special treat, as we were recognized for our outreach efforts by the Society itself, represented by President Michael Goldburg.
Copyright (c) 2010, Society for Neuroscience. All rights reserved. Photo by Jeff Nyveen.
Copyright (c) 2010, Society for Neuroscience. All rights reserved. Photo by Jeff Nyveen.
The highlight of this conference for us, of indeed all the conferences we’ve been to, was meeting the second most famous Neuroscientist ever. Yes, none other than Nobel LaureateEric Kandel. When we saw him at the beginning of the Presidential lecture, making rounds and shaking hands with the other famous neuroscientists, we snuck up behind him and slowly turned up the speaker on our SpikerBox. When he turned around, we said,”Sorry to interrupt you, Professor Kandel, but we were just wondering if you’ve ever seen neurons before.” He didn’t skip a beat; he saw the real-time spikes on the iPad, and said “My, those are beautiful! Spikes at Neuroscience! You’re the ones who should be giving the presidential lecture!” He touched the cockroach leg to see if he could evoke a neural response, and he was convinced. We then sat down. Thanks Professor! We’ll keep working hard! Props also to Jeff Nyveen, photographer for the meeting, for quickly grabbing the shots for us.
Copyright (c) 2010, Society for Neuroscience. All rights reserved. Photo by Jeff Nyveen.
Copyright (c) 2010, Society for Neuroscience. All rights reserved. Photo by Jeff Nyveen.
For the past nine years, Tim has had a subscription to Wired Magazine, and he always read the articles on the internet revolution, learning about the drama, personalities, and technology involved with the rapidly changing world of computers. Longingly, he has despaired, wishing neuroscience and biology R&D could be similarly fast with low barriers to entry. We at Backyard Brains are trying to change that, and so it was a special treat this month to be included in the print version of Wired. If you strain your eyes on page 153, you’ll see a postage stamp sized picture of the SpikerBox in the 100 geek gifts for the holidays. Perhaps the soldering iron will replace the wiimote for some folks this year [Disclosure: we love the wii too and take no political/intellectual stance regarding video games].
We also recently returned from the Society for Neuroscience conference in San Diego (full post coming soon as we round up the pictures), and we give thanks for the Society for sponsoring our trip through the Next Generation Award,and to the Journal Neuron, which also sponsored us through the Anuradha Rao Memorial Travel Award. We’re working hard; thanks true believers!