tl;dr: I made 3D printed, bluetooth game show buzzers for playing The Voice at home, powered by Adafruit Circuit Playground Bluefruit boards and a laptop. Bringing Reality TV to Reality If you ask me, combining a makeshift karaoke setup, cheap beer, and good friends all but guarantees a fun night. Ok who am I kidding, my college days are well behind me – decent beer. Anyway, toss in some random swivel chairs and before you know it, you’re playing your own version of The Voice™ wishing you had some big red buttons to smash. That’s the origin story of this Continue Reading
Electronics
Making it rain with Software Defined Radio
For about the same cost as of case of PBR, you can buy a cheap software defined radio called the RTL-SDR. With this simple USB dongle, you can turn your PC into a wideband radio scanner and use it to sniff out RF signals anywhere from 25 MHz to 1700 MHz. In case you’re not familiar, an SDR receiver works a lot like a traditional radio transceiver, except that most, if not all, of the signal processing that would normally happen in hardware, is done with software instead. Essentially, an SDR receiver captures the raw radio signals (using a tuner), Continue Reading
A wireless water level sensor for the Internet of Tannenbaums
I rigged up a crude little water level sensor to monitor my Christmas tree and send me alerts when it gets thirsty. With the help of two strips of aluminum stuffed in a FoodSaver bag, an Adafruit HUZZAH32 – ESP32 Feather Board, and a little Arduino code, our humble tree has become part of the IoT revolution! Physics lab flashback The sensing probe that goes in the water is basically just a parallel plate capacitor straight out of undergrad physics. The water flows between the plates and works as a dielectric. The relative permittivity (aka dielectric constant) of water is Continue Reading
Oldsmobile Modsmobile
If there’s one good thing about driving a $500 POS with no A/C and a driver’s door that doesn’t open, I guess it’d be that you can’t really make it much worse. Before the brakes blew out for the second time, I made a couple mods to my 1995 (??) Cutlass Supreme, aka The Stallion. Since the Cutlass was already an extremely high-performance machine, and that fact that I know next to nothing about auto mechanics, the upgrades were purely electronics related. CarPlay The first order of business was to hack in an aux input into the radio, which only Continue Reading
Battery pack spot welder
This one might have to be filed under the fail column – at least for now. While throwing around some ideas for the next incarnation of DJ Big Gulp, I decided I needed to figure out how to make my own lithium ion battery packs. I bought a couple of INR18650s, some battery protection boards, and some nickel strips to connect them together. All I needed was the welder… The showstopper I thought it might be safer to try this rig out on some alkaline batteries before diving straight into the lithium ion. At first the welds seemed to be Continue Reading
DJ Big Gulp
Need tunes on the river? DJ Big Gulp’s got you covered! Bluetooth enabled and ready to party for hours!
Light Up Bean Bag Toss
A while ago I got my hands on some scrap photoelectric sensors from work. The defects were only cosmetic, so I mounted a pair of them to a flimsy bean bag toss (aka cornhole) set I had made a couple months before. I drilled 12 small holes in a circle around the main hole and filled them with LEDs. I added a little box with some batteries and a couple 555 timer circuits so that the LEDs would flash for a few seconds whenever a bag went through the hole. The effect was kinda cool considering it was mostly just Continue Reading
LED Matrix
Not sure why, but I’ve always thought making a huge LED audio spectrum analyzer would be cool. With that goal in mind, I picked up some dot matrix LED blocks and started breadboarding. This project started long before the days of Neopixels, so the most advanced tech on my PCB is slew of LM317s for current limiting and a handful of high-current shift registers for multiplexing. As you can see, there was a pretty bad ghosting effect as the letters scroll by. It took me a while to figure out that the display needed to be left completely blank for Continue Reading