Member Since: May 29, 2007

Country: United States



Born in California, raised in Minneapolis, moved to CO 13 years ago. Wife Becky, daughter Claire, son Ethan, dog Merlin. Trevor is my brother-in-law, but he may not want anyone to know that…


Director of Engineering


SparkFun Electronics, HID (Assa Abloy), Bearcom, Jon Dressel & Associates, Music tech.

Spoken Languages

English, bad English

Programming Languages

C, bad C


I don ’t associate well.


CU Boulder, Front Range CC, Mpls CC, NEI (in MN, called something else now, I think)


RC planes/sailplanes/cars/helicopters, guitar, astronomy, electronics, scifi, paranormal everything, slot cars, big cars



Care to take a peek under the hood of reality? Hall effect and Lorentz force are big news in the land of the tiny.

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We tend to over-simplify the act of dropping an LED into a circuit. But do you know what all of those specs in the data sheet mean?

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You'd normally run them in series. But can you run them in parallel?

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Want to get started with car hacking? This video is for you!

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Seemingly magical behavior from 50's era tech. What darkness lurks beneath?

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Heard about CAN bus but don’t know what all the hype is about? This video’s for you!

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Next Fall's AVC is starting to take shape. We've seen the future, and the future is... GOATS!

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Looking for a beefy, wired data bus where RF won’t cut it? We dig into RS-485 and explore how it works and why it just might be the one you need!

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Without phase-locked loops, we’d all still be living in caves, just getting by with stone knives and bearskins.

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Why do we collaborate?

Is there more to the collaborative process than just getting a project done?

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Behold: The SparkBowl

In honor of last weekend's Super Bowl, we give you a slightly more techy take on games you can play with a football.

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To honor our 15th anniversary, Pete digs into the electrical properties of crystals.

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The convenience of advancing tech can kill a good nostalgia project...but it's not quite dead...

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How slowly can you clock an ATmega328 and still have any functionality?

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OK, it’s not a thing. But if it were, it might look like this.

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Harris Kenny of Aleph Objects shares some history and philosophy behind the success story that is the Lulzbot line of 3D printers.

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I design and build a headphone amplifier, and go on a journey of self-discovery (and learn some hard lessons).

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Is there a “right” way for an open project to go closed?

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If the spooky messages you’re getting from beyond the grave seem vague and disjointed to you, maybe some blinky lights can help to accent the important parts. #funkydemonspeak

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Find out what happens when Pete takes on Big Bluetooth.

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The Case for Patents

One open source guy's opinion on whether or not we should have these things at all

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There's so much arguing over code on the internet. Let's try to get to the bottom of the debate.

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What has Pete been up to? Playing with flying robots, actually.

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Rules updates, scheduling information, and some questions answered

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A look at what classic AVC competitors will be facing on September 17

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We take a trip to check out a different version of DIY and make some new friends on the way.

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Pete Dokter and Jim Lindblom tour the MIT Media Lab, as well as the greater Boston technological tundra.

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Another AVC Update

We flesh out the AVC prize structure, plus the trials of Pete's first attempt at competing in the AVC.

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AVC 2011!!!

The flood gates are open for AVC 2011.

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Solder of the Ages

Building your latest satellite with old solder? You might want to think it over.

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What to do with an overflowing cup of electronics

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Pete and Ryan's Excellent Sketching in Hardware 2010 Adventure

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Custom stingray covered gaming watch, plus Antimov videos now accepted

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Antimov Competition

Introducing the Antimov competition! Who can build the robot that does the most insignificant task, fail spectacularly, and then self destruct?

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Director of Engineering Pete Dokter plots the data from a rocket launch - and suggests a new method for testing SparkFun products!

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Lumenati Hookup Guide

October 12, 2017

Lumenati is our line of APA102c-based addressable LED boards. We'll show you how to bring the sparkle to your projects!

Series and Parallel Circuits

August 20, 2013

An introduction into series and parallel circuits.
  • Oh… OK. Yeah, that sounds like a really good candidate for a hall plate. I’d be very curious to hear the results.

  • Mylar… that’s an interesting choice. Primarily for the thickness? How big is the piece you’re using? What kind of resistance is it offering and how much current are you pushing through it?

  • Dude that is so AWESOME! I mean, you’re not there yet, but still really cool! I didn’t even get to see induction. But yeah, the field ultimately has to be stationary to prove anything here. And I still think the foil has to be super thin - rather, you’d get better results with progressively thinner pieces of foil.

    I really want to build a Thomson Galvanometer. Can you imagine a 30-foot needle? You could build your own femto-ammeter.

  • LOL You went easier on me than I thought you would!

    1) Thanks! The demo… meh. I mostly wanted to see… anything. But it clearly takes more effort than tin foil a scope and a magnet. But how cool would it have been if it worked?

    2) I was really trying to steer clear of anything that looked like vector math and keep it as conceptual as possible. But you just had to bring us there… ;) As far as being a math nerd, ain’t a thing. I’ve been eyeing my calc books for a little of the ol' self-inflicted pain. I really do believe that math can be fun (certainly algebra - that’s just a game!).

    3) I dunno… that almost would have been too much effort. Ironically, I would have totally gone the distance to hammer the tin foil thinner, given a little more time. So maybe too much money.

  • I don’t know that there was any one problem (I think maybe it was entirely built of problems). But the dimensions of the foil vs the size of the magnet is a good place to start.

  • 1) You attach it to the negative side of the input of whichever channel you’re looking at. But I would caution you to read up a bit on the MP3 Trigger and understand the use of GBUF (you wouldn’t use it here) and some of the jumpers on that board before attaching it.

    2) The amp board really needs a good 12V or better to give good performance, and that’s the max rated for the MP3 Trigger. But the regulator on the MP3 Trigger is linear, meaning that it’s going to drop all of it’s extra power as heat, and kind of a lot IMO. If it were me, I’d probably start with a larger supply, like 12-15V, and regulate down to something more reasonable for the MP3 board, like maybe 5-7V.

  • I’m shorter in real life, right?

  • Hey ‘773! Thanks for stopping by and for dropping some good knowledge on us! I taught you something? You honor me, sir.

    Yeah, iterating with fixed values blows. I’ve done it with a pot, too, But these days I’d much rather use PWM or an addressable. Sooo much easier.

  • Hey ‘773!

    For the “who’s turn” indicator, I think the problem you’d run into is that people will forget to hit the button (or whatever) to advance the indicator. So that would really benefit from some kind of automation, and I’m not sue what form that would take. Maybe some voice recognition of the words “aw, you suck!” or some variation on that theme… just thinking outside the box, here. Maybe an accelerometer under everybody’s chair to sense their cycles of agitation, like the person that just relaxed just finished their turn. Or some kind of IR or thermopile to register the heat coming off the players' heads? But alcohol will probably mess that up (sugar makes my head sweat - truly weird).

    As far as the github jab… yeah, you’re right. But that’s the sort of project that I’m likely to put the barest amount of effort into. I need a light, how quickly can I pull this off and then forget about it? I’m definitely not trying to justify, but I am admitting to a shortcoming with regard to personal work. And I know I’m not alone…;)

  • Thanks much!