From Jeremy S. Cook on the Hackster blog:
As hackers and creators, we sometimes get asked the question “why?” While many of the gadgets we make do have a specific purpose, many of them definitely don’t, and are made because we wonder if something can actually be done. This giant three-key mechanical keyboard would certainly fall into that second category, and though I can’t think of a practical use for it, I still find the device quite entertaining.
The heart of this device is a trio of “Big Switch” devices from Novel Keys, which are four times larger in length/width/height than what you’re used to typing on. While that might sound only sort of interesting, that translates to 64 times normal size in volume; plus they include similarly ginormous keycaps. Glen Akins, inspired by a similar project on Adafruit, decided to build his own 3-key array, with a PIC18F14K50 chip providing an interface between the keys ans USB input.
The housing is made out of aluminum, and sits at an angle to the user for excellent ergonomics — if you happen to be a giant, and only use three keys at a time. While the electronics are fairly straightforward, these large keys are electrically quite noisy. Debounce code was added to combat this, reducing the letters per keypress from a range of one to three to only a single character.
Read more on Glen’s own Photons, Electrons, and Dirt blog:
Software Defined Radio (SDR) project by Eric Brombaugh:
This is a test prototype for experimenting with Software Defined Radio (SDR). It is composed of several boards that are described in detail elsewhere on this site:
Combined with suitable firmware and FPGA design, these boards comprise a receiver capable of capturing 20kHz of signal from DC to over 1GHz, demodulating it with a variety of formats and driving high-quality audio.
RF input from the antenna can optionally be tuned down from VHF/UHF frequncies to an IF frequency in the HF range before passing to the ADC.
Raw HF or downconverted VHF at an IF of 5MHz is digitized to 14-bit resolution. The maximum input signal allowed without exceeing the range of the ADC puts the 0dBfs point of this system at -10dBm in 50 ohms. The ADC runs at 40MSPS with a resolution of 10 bits, providing approximately 60dB of dynamic range and 20MHz of bandwidth which places the quantization noise floor at about -70dBm.
From the ADC, data passes into the FPGA. This is an iCE5LP4k part which provides 20 4kb RAM blocks and 4 16×16 MAC blocks which are essential for the DSP required for the downconversion. In the FPGA the ADC data is pre-processed to a sample rate appropriate for the MCU. Figure 2 below shows the primary components of the FPGA design.
Valerio Backslashnew has designed a small dock for the Onion Omega 2 and 2+:
I needed the smallest dock i could do, that featured:
- Type A USB host
- Micro USB for power
Here’s what i came up with, i called it dock\new.
It has an onboard linear voltage regulation (i didn’t bother going with a switching one for such low power), magnetics integrated in the RJ45 connector to save space, USB host ESD protection (diode array), USB host PTC fuse.
On the left side there is the RJ45 connector and nothing on the back side of the board, so that you can easily access the MicroSD card on the Omega 2+.
On the right side (the antenna side of the omega) you have the USB type A connector, facing outwards, and the microusb connector for power, facing inwards.
The project is open source (CC-BY-SA 4.0), and the KiCad schematics, board layout and the other files are available on GitHub:
5N44P has shared the board on OSH Park:
Alex on Hackaday.io is working on a smart miniature (DIP6) 5×7 LED Matrix:
This project is based on my #reDOT project. Basicly it is a 5×7 SMD LED Matrix an a microcontroller on one PCB. I started wirh 0201 LEDs (see first project log), but this was not reliable. So a second version with 0402 is in development. 0402 LEDs do have some benefits over 0201:
- bigger and you can solder them better
- more colors availible
The microcontroller (a low coast STM8) drives all LEDs directly with multiplexing. For controlling a UART interface is available. The dimensions are like a DIP-6 package. For easy connection of multiple PCBs, the pads are castellated. Also the supply rails are available on both sides. So multiple of these display can be soldered together to a bigger display without the need of additional wiring.
Jens Hauke designed this charlieplexed 20 LED blinker controlled by an ATTiny45 for the Hackaday Coin Cell Challenge:
This is a small blinky with 20 LEDs powered by one CR2032 coin cell
and with an ATTiny45 brain. The firmware is written in plain C and
compiled with the avr-gcc toolchain. The PCB is a two layer design made
Space efficient daisychained LED placing with shared anode/cathode soldering pads.
Firmware and gerbers are available on GitHub:
Jens has shared the board on OSH Park:
Here is a video of the LED in action:
A holiday project by Dan Hienzsch (@rheingoldheavy) to build a little Snowbot with an adjustable speed larson scanner for an eye:
The Snowbot has three major subsystems: Power and Timer and Display.
The power subsystem uses a 3.7V LiPO battery boosted to 5V with an SC4503 boost converter to power the fully analog circuit. It requires a set of passive components in order to generate the higher voltage.
The timer subsystem is comprised of a 555 IC that generates a clock signal. The speed of the clock is adjusted by twisting the potentiometer (the nose of the snowbot). The clock signal ticks through the outputs of a CD4017 decade counter, lighting each LED in sequence, then moving back through them again.
The display subsystem involves taking the output of the CD4017, and directing it to six red LEDs in the form of a larson scanner. In addition to lighting the LED, the current also charges a 22uF capacitor through a diode. When the output moves to the next LED, the cap discharges through a 2.2K resistor (part of a resistor network), fading the LED out gracefully.
The 1bitsy and Black Magic Probe are now available in our store:
Open-Source Miniature Breadboard Friendly ARM Cortex-M4F Dev Board with 1MB Flash, 196kB RAM, 168MHz, floating point and more.
Plug and Play JTAG/SWD USB programmer and debugger with a built in GDB server and TTL level UART to USB adapter.