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



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.
  • Thanks very much!

  • 1) It’s half-duplex. If you want full, you gotta run another twisted pair. Master/slave is determined by the protocol the user decides to employ. I’d prolly do it that way. 2) What happens? Also determined by the user’s code. It’s not like the inverted data is electrically hazardous, it’s just nonsense. But it’s not like you’re going to have random strangers walking up to your RS-485 bus, talking with a funny accent… Bonus: Correct.

  • Cassy makes me turn off my psychedelic-proggy stuff before recording, so it’s not incidental background. But I’m unwilling to turn the volume up enough to hear whatever it is. I don’t think I can handle my own voice at high volume.

  • ‘773! Good to hear from you. 54 was Phase Locked Loops. As for any listing difficulties… dunno.

  • Truth be told, I threw that 7805 in there in a hurry and never got back to put the caps in. I didn’t want to lie about it when I drew up the schematic… and now you went and called me out!!

    Shortcuts, kidz. They can bite you in the backside.

  • I thought for a long time that I had been victimized by such a device. I would periodically hear such chirps in my office, but I never went the distance to actually look for anything cuz I knew it would be impossible to find. Then one day I figured out that the automatic light shut-off circuits we have installed here emit that noise in a lead-up to turning off the lights. This place has made me so paraniod…

  • Next trick: glue an ol' guitar to the ground. Just not an expensive one.

    As far as the ProMini regulator, (12V-5V)*(30mA) = 210mW. On a SOT23-5 package, 210mW is screamin' hot. But it’s a non-issue on a TO-220.

  • LOL that’s good. Somebody tried something similar on me a while back, but they failed to consider how much their battery would drain before I got in.

  • That’s one approach that will work. But the battery itself is rated for 25C discharge (if you put any stock in C ratings). The servo is unlikely to draw 25 amps, though I’m not sure what its stall current is. Having a second regulator was easily sufficient - at least on the bench.

  • Why not? Only because I don’t have one of those as easily accessible as building my own circuit. I’ve got a pile of LM317’s, but I’ve got no languishing BEC’s lying around.