About

Hi, I’m Daniel! I’m from Argentina and I like working on electronics, playing guitar and board games, cooking, and drinking mate (not “mate” like “friend”, but like “the drink made with yerba mate”).

Visiting my friend Buc-ee on the way to Austin

Background

I moved to the United States (Iowa of all places) when I was seven years old. I lived there until I finished high school, at which point I moved to Los Angeles for college. I graduated with an exciting new electrical engineering degree and I’ve been working as a hardware engineer at a startup in the bay area since then.

Previous Projects

I started writing this blog in 2020, here’s some of the (non work) projects I’ve done before I started documenting them here.

College Projects

  • RoboTrike – This was my first “EE” project. We were given a board with an Intel 80188 processor, a keypad, motor drivers, serial chips, and some other chips that could be used to control an omni-directional robot. We had to write all the x86 assembly code required to do that.
  • Oscilloscope – This was the first board I’ve ever designed! We were given the code and we had to design all the hardware for an Altera Cyclone 3 FPGA-based 15 MHz oscilloscope. I used an old ratty FedEx screen (because it was free and my TA had used it too) and my button layout was completely unintuitive, but otherwise it worked OK! I have the full set of documentation if you’re interested and/or bored.
  • Dog Bowl – We were tasked to design a dog bowl that would be able to identify different dogs and open when they were nearby for our analog project class. Mine worked OK but it looked kind of messy because I built it using pieces of wood I found laying around my dorm (hmm – I’m starting to see a pattern here).
  • Bubbly – This was a project I did for my stepdad using an Atmel chip. It measures a noisy square wave and reports the duty cycle. I have very extensive documentation (180+ pages, including all the schematics, layout, and assembly code) for you to read!
  • Distortion Pedal – I built a guitar distortion pedal (I called it “red herring”) for another analog circuit project class. This one actually looks quite nice and it’s the only one of the bunch that I use, but the circuitry is pretty simple.
  • Electric car project – This was a group (40+ people) project where we tried to build a car to enter the FSAE electric car competition and failed. But it was fun, we got to mess around with a 300V, 1kA battery pack!
Documents
Oscilloscope full documentation including FPGA and hardware description and assembly code (PDF)Download
Bubbly technical manual including hardware description and assembly code (PDF)Download
Gallery
  • My first board! This is the oscilloscope board without the clunky display attached.
  • Underside of board showing that back then I made plenty of mistakes, too
  • This shows the back of the old FedEx display (look at the video if you want to see how bad it actually was at displaying things)
  • “Red Herring” guitar distortion pedal
  • Dog bowl – duck tape is your best friend
  • Bubbly “duty cycle measuring” project

Recent Projects

  • FPGA Audio Effects – Right out of college I decided to work on an Altera Cyclone V FPGA-based audio project. The basic idea was to take an audio signal from my guitar or another audio source and be able to do all kinds of digital filtering and effects inside the FGPA. I wanted to apply some of the things I’d learned in my digital signal processing class. Unfortunately, I dropped it after working on it for a few months because work ramped up. The files are still on Circuit Maker since that’s what I was using at the time (I really liked Altium in college).
  • Christmas Tree – This was a fun little project to familiarize myself with Arduino. I bought a cheap “tree” from Target and attached a bunch of LEDs that would blink in various patterns. I used a teensy board for this (and paid my friend in fried chicken to write the code…).
  • Compression Pedal – A few years ago I decided to make a simple guitar compression pedal. I have a Yamaha THR5A amplifier that I really enjoy, and I’ve liked playing with the compression settings on that a lot, so I decided to learn more about it. You can find all the files for the project in Circuit Maker here. The basic circuit is an op amp with a JFET as a variable resistor in feedback that drives the input higher or lower to keep it at a near constant amplitude. This worked well, but I never got around to tuning it and making a nice enclosure for it, which is a bit of a bummer. I’d love to pick this back up soon and wrap it up since I still have the hardware!
  • Wrapping up the Christmas tree project
  • Christmas tree project in action
  • The complete tree project (electrical tape is your second best friend)
  • Debugging the basic op amp JFET circuit for the compressor pedal at home, using my phone as an audio signal generator (isn’t that cool?)
  • The board for the compressor project
  • The compressor board with all the components loaded in