Blog Posts

PJRC forum member blackcoffee has created a Thermal Imaging Camera based on Kris Kasprzak’s original Teensy 3.2-based project, using the same AMG8833 infrared array sensor, but updated to use Teensy 4.0.

The unique enclosure holds a homemade PCB, in addition to the sensor, batteries and LCD display. STL files and Gerbers can be found on Thingiverse, and a demonstration of the device in action can be seen in the video below.

Ted Fried of MicroCore Labs picked up a 1975 HP 1600A/1607A logic analyzer set over the weekend, his first instinct was to throw a Teensy at it!

The Teensy 4.1 was just the thing to provide 32 data signals and two clock outputs to the HP1600A logic analyzer, which provided some stimulus to the device and tinkerer alike, but then Ted discovered the “MAP” function! This allowed him to write to a 64×64 pixel map, the results of which can be seen below. This evolved into full-on monochrome BMP display, including a utility to convert the files to the MAP format, as seen in the first image. We can’t wait to see what Ted does with it next, and we’re guessing we’ll find out what that is on his blog.

Ted has is someone you’ll find all over our blog and forums with many interesting projects.

Edward Wang had a dream of owning a Roland Juno-106, buy no money to buy one. So actually maybe just one thing: an extreme desire to recreate the sound he heard on a Tame Impala album. Thus began the teensy-juno, a polyphonic synthesizer modelled after the Juno-106.

In addition to 8-voice polyphony, the teensy-juno features a flanger, offset, depth, and rate parameters, pulse, saw, sub, and noise oscillators, high- and low-pass filters, an ADSR envelope, pan, portamento, LFO with delay, and voltage-controlled filtering (VCF) by envelope, LFO and mod wheel. All these synth features are implemented using the Teensy Audio library.

In addition to the source on GitHub, there is an endearing account of the project’s and tribulations on Edward’s blog, as well as a video version, below.

Brendan Riuz is working on a project to allow a 16-station turret to be added to a CNC lathe. This requires a microcontroller to interface with the motion controller, stepper motors, and more, for which he chose a Teensy 3.5.

The solution is all-electric, with no compressor or hydraulics required, and features four different ways to interface with the CNC controller, with as few as three wires. Tool changes are possible in five seconds or less from eight 3/8″ and eight round stations.

A Pololu DRV8825 stepper motor driver carrier is included. A built-in voltage regulator can use up to 35V external DC power. See it in action in the video below.

Ledmasters has created a chronograph for measuring bullet speed, using a Teensy 4.0 connected to an Adafruit Feather M0 via RFM69 433MHz radio modules.

Stats are displayed on a 3.2″ TFT display, and can be printed via an integrated thermal printer. Piezos attached to PET film are used to measure the bullet strike and elapsed time over a 12″ span. More information about the project can be found in the original forum thread.

Rune Kyndal turned his 1990s era plamtop into a functional Linux machine jamming a Teensy LC, USB hub, and Raspberry Pi Zero W into the small space created by gutting the original electronics.

The HPi95LX (get it? Pi?) crams a 4.3″ 800×480 color LCD (up from 240×128 monochrome!), stereo speakers and USB mic, two USB ports, a full-size Ethernet jack, DE-9 RS-232 serial, and more into this diminutive form factor.

The Teensy is connected to the keyboard membrane to convert it to a USB keyboard for the Pi. Read more on the project’s Hackaday page.

Lazer Tag infrared gun system was one of the hottest new toys in the 1980s, with Tiger’s Lazer Tag Team Ops (LTTO) attempting to build on the franchise in 2004. Fast-forward another couple of decades, and Daverlee brings another great leap forward with his Teensy-based overhaul of the LTTO hardware.

With gameplay based on the Halo series, each gun contains a Teensy 4.1, LiPo battery and charging in place of the original AAs, a color ST7789 LCD substituting for the original monochrome display, a class-D amplifier and vibration motors for audio and haptic feedback, an RFM69 radio for communication, and NeoPixels to indicate team alliance and player number, as well as damage.

Adafruit’s Circuit Playground Express powers base stations, with RSSI-based “radar” to determine player position and weapon range. More information can be found on the project’s Hackaday page.

Continuous Wave or “CW” is a simple way to transmit Morse code over radio waves, and is still popular today, including in the form of contests, where enthusiasts race to generate codes as quickly as possible.

In addition to these encoding activities, decoding is also necessary if you want to understand what was transmitted, which is where PJRC forum member pd0lew’s CW decoder project comes in handy.

The project is based on a Teensy 3.6 + Audio Adaptor Board, with additional automatic gain control (AGC). Once the signal is decoded, it is output to an RA8875-based TFT LCD via SPI, which can accommodate five lines of text, and it can also be read over USB. A custom CNC-machined PCB ties it all together inside an attractive aluminum enclosure. Find out more on the CW monitor project page, or in the video below.

Before this final version housed in a beautiful enclosure, earlier versions were made without any case, and with a milled PCB and die cast enclosure.

In this video the older version can be seen and heard (starting at 0:47) displaying the Morse Code.

Noisio is a kit maker of minimalistic audio kits inspired by classic circuits like the Atari Punk Console. Funkstern Plus radio art object is the latest example of this design maxim.

The Funkstern Plus is bespoke project combining synthesizer, FM transmitter, audio player and 7-channel stereo mixer. It was commissioned by the Rundfunkorchestra for the Bauhaus University Weimar “Archiv der Moderne” collection.

The instrument is also used by the Rundfunkorchestra in live shows, and recently won the Saxon State Prize for Design 2023 in the Digital Design category. More information can be found on noisio’s blog, as well as in the video below.

While attempting to understand the mess of wires that is the Apollo-era space program Up-Data Link Confidence Test Set, Ken Shirriff decided to automate the manual probing process with an automatic connection tracing system that he calls the Beep-o-matic.

Ken Shirriff’s blog is a veritable smorgasbord of fascinating in-depth retrocomputing content, and he also documents his work extensively on Twitter. His reverse engineering of the Apollo Guidance Computer is a particularly fascinating project, and it is here that our humble Teensy 4.1 comes into play!

By combining three 16-bit PCA9555A GPIO chips with the appropriate connectors and a Teensy 4.1 over I2C, Ken can scan through all 47 pins in under a second, rather than laboriously listening for a multimeter beep while probing each manually.

A couple of Python scripts capture and process the output, and voila, you have … an extremely specific tool that is unlikely to be of use to anyone else on the planet? However! The same concept could certainly be applied to other reverse engineering problems, so take a look at the project details and code on GitHub, and let us know if you end up adapting the idea for other uses!