Want to improve your posture? This wearable posture sensor from Coretech Robotics will remind you whenever you slouch and help you maintain a good posture: Posture sensors/monitors have been a recurring theme on this blog. They are supposed to remind you of your posture and prevent you from slouching, which can be a cause for […]
Category Archives: DIY
PWM dimmer for RGB LED
Lukas Fassler has designed and built a PWM dimmer for RGB LED: In my last post I’ve described the design and construction of my LED dimmer project. This project here is similar but a bit more involved. It controls RGB LEDs so it can not only change the brightness but also the color of the light. […]
Instruments for the GSXR
Josh from imsolidstate made a new dash panel for his streetfighter based on an ATmega128, a Planar EL 160×80 display, and an Epson S1D13700 controller: Since the GSXR is now a street fighter the factory gauges won’t do, and I wanted something I could log air/fuel ratios with so I can jet the bike. I […]
Mullard 3-3 Amplifier project (part 2)
Dilshan Jayakody writes: This is a second article related to Mullard 3-3 Amplifier Project and in this article we introduce HT transformer and HT power supply related to this amplifier. As mentioned in previous post, power supply unit of this tube amplifier is constructed using 400V 5A bridge rectifier, 220µF (400V) and 82µF (400V) electrolytic […]
An S/PDIF sound card using the PCM2906
Joesugar writes: When S/PDIF became available in the Teensy Audio Library I thought this might be the solution to ground loop problems I’d been having when interfacing projects to my PC. However, I quickly realized I didn’t have any sound cards with an S/PDIF interface. In the belief that I’d rather build than buy I decided […]
PWM dimmer for LED lighting
Lukas Fassler has published a new build, a DIY PWM dimmer for LED lighting: I have recently moved to a new apartment and was looking for a PWM dimmer to control some 12V LED strips. I thought that should be easy enough nowadays but it proved more difficult than I thought. All I found either didn’t meet […]
Quantifying cooling
Chris Palmer (a.k.a nophead) has designed and built this coolometer project to quantify the cooling effectiveness of various fan: I was wondering about how I was going to calibrate the airflow reading but then realised that the flow rate is not actually what I am interested in. It is the cooling effect the airflow has, which is […]
Programmable CW Morse Keyer / beacon
Marko Pavlin has designed a Mini USB dongle with STM32F0xx , he writes: Mini USB dongle with STM32F0xx is suitable many for simple, mini projects. I attached speaker to Timer14 PWM output (Pin PA6) and LED (or optocoupler connected to PTT) to GPIO pin PA0 The provided software is based on USB Virtual Com Port (VCP) device. […]
Nixie thermometer
Luca Dentella has developed a Nixie thermometer to measure the temperature of the liquid cooling system, that is available on Github. I decided to log the design and the development of the project in ten blog posts. They show my “divide et impera” approach: I divided the whole project in small tasks (drive a nixie […]
Happy Valentines day!
Sjaak built this blinky heart for his girlfriend this Valentines day as having a girlfriend in Valentines is always fun and you can even try a virtual girlfriend like queenoftheblack if that’s your style. It is based on a MAX7219 and a PIC16f1823: My girlfriend persuaded me to start this hobby side project while looking […]
‘Magic tree’ project
Dilshan Jayakody has published a new build, a ‘Musical trees’: “Musical trees” is a part of creative arts installation and this project is capable to produce different audio tones by detecting human touch to its attached plants. Existing version of this driver is capable to monitor 8 plants and produce different sounds for each plant. […]
mavroOBD, an open source Arduino compatible OBD/Can-Bus module
Mavromatics’ open source project designed to “hack” your vehicle, that is available on github: The goal of this project it to create an Arduino based OBD port module that can be used to enhance a vehicles capabilites. For example, if you want door locks to close when moving faster than 5mph or to invoke/emulate certain […]
flip-flop/BCF project
Ray over at the diyAudio forum has been working on his flip-flop/BCF project: I’ve just finished a project to roll up the developments into a more ‘finished’ build, feeding the balanced outputs from the flip-flop board into a Broskie BCF buffer stage. I’m using Nicks MJ Statistical Regulator for the B+ and one of Andrew’s indirect filament […]
Building a low cost wifi camera
Johan Kanflo designed a Esparducam board and built a low cost wifi camera with an Arducam Mini and a ESP8266 Wifi module: Sometime ago I came across the Arducam Mini which is quite a nice camera module from UCTronics. It is a small PCB with a two megapixel OmniVision OV2640 sensor, an interchangeable lens and an FPGA to do […]
Arduino MPPT solar charger shield
Lukas Fässler made an MPPT solar charger project and wrote a post on his blog detailing its assembly: The basic idea behind an MPPT solar charger is simple. A solar panel has a certain voltage (in the region of 17 to 18 volts for a 12 volts pannel, somwhat dependent on temperature) at which it […]
Simple small QRO for HF
Marko Pavlin has been working on a HF amplifier project: I followed the ARRL Homberw challenge 50 watt aplifier entry. It is low cost, simple HF linear amplifier designed and built by the author as an entry in the ARRL’s 2009 Homebrew Challenge contest. The requirements of the amplifier were: 40 meter band 50 watt output […]
ESP8266 mains energy monitor
A ESP8266 mains energy monitor project by Brian Dorey: As the new solar logger did not have this functionality we decided to design a new data-logger that would measure not only the mains current usage but also keep track of the electric meter and gas meter so we can easily see how much energy we […]
Freescale’s sensors breakout boards
Freescale’s sensors breakout boards from Juan Ignacio Cerrudo: MMA8541Q, FXOS8700CQ, MPL3115A2 and Logic Level Converter: The MMA8451Q is a low-power, three-axis accelerometer with 14 bits of resolution. It communicates over I2C, has built in tilt/orientation detection and also tap detection. More details at ssihla site.
Mullard 3-3 amplifier project (part 1)
Dilshan Jayakody has published a new build, a Mullard 3-3 amplifier project: Mullard 3-3 is quiet popular 3W tube amplifier introduced by Mullard Ltd in 1956. A schematic and design detail of this amplifier is available in “Mullard Circuits for Audio Amplifiers” book and in National Valve Museum article. This amplifier is based on EF86, EL84 vacuum […]
A 3.6V LiFePO4 charger for under 50c
Nerd Ralph built his own 3.6V LiFePO4 charger: I like LiFePO4 batteries. They have a rather flat discharge at around 3.2V, which is ideal for powering 3.3V devices without a regulator. You can also use them in devices that take 2 standard AA cells by using a blank shunt in the 2nd battery slot since 2 […]