Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

Arduino driven bathtub

If you want to relax on bath, you need right water level and temperature. If you add bubble, then it’s supper. raptor_demon is working on Arduino based bathtub controller. He wants to set up system where bath could be prepared with single button click and with Ethernet support even remotely. First o all, instead of using standard Arduino he built his own custom board where all controller parts fit in. He added three mechanical relays that control fill valve(or pump), Soap dispenser and drain valve. Temperature of water is taken with DS18B20 sensor. He also added 343MHz receiver for remote in tub temperature. There are plugs available for flow meter and Ethernet – those aren’t implemented yet. He placed controller in to laser cut plywood enclosure with Adafruit LCD screen shield in front. Continue reading

Wireless Temperature Measurement

This one is a little different project related to temperature measurement. Apart from being wireless, it measures both indoor as well as outdoor temperature. It’s made in two parts. The first part consist of the temperature sensor and the transmitting module, while the other one has the receiving module, an analog sensor and the display. The parts used in this project are easily available at the local hobby shop. Hey comprises of two Arduino, an lm35 sesnor, a ds1820 digital temperature sensor, an lcd and a receiving and transmitting module For the project, you will require three sets of library. Two are for digital sensor and one for rf module. All of them are available on the project website. Overall an excellent project for beginners who has just started to learn Arduino. It will teach you about LCD interface, wireless interfacing and also sensor interfacing. To those who want to try the code along with complete schematic is available on the project website. Continue reading

A DIY Polar Plotter

A polar plotter is an Arduino based plotter that has an advantage of being portable and still being accurate. Apart from being portable it looks really beautiful and powerful enough to use and is a lot faster than traditional plotter. The code of this project comprises of two parts, the Arduino project that controls the plotter and other being a java project used for generating font-data in a format readable by the Arduino program. The plotter is powered by an Arduino Uno along with two heavyweight stepper motor which seems to be producing a lot of sound. Apart from this, it features a complex looking, but easy to make mechanical system which also include gears. There are also push buttons provided for arm extension and also rotation and also to trigger the plotter. The Arduino program implements sort of the Bresenham’s line drawing algorithm. In the implementation, each line segment is split into 1/8mm in the least steep direction which makes it easier for the plotter to draw smooth lines. The plotter is amazingly fast, considering the size of it. Continue reading

Monitoring GitHub activity on RGB LED matrix

Jack wanted to monitor his GitHub activity in more visible way, so he build an RGB display based on TIM board. Display is driven by Arduino using single pin in serial mode. The interesting part in this project is how Arduino connects to GitHub API to get status. It is done by using smart device – called Electric Imp card. It is SD card sized device that allows easy Wireless communications. IT can be programmed using “Squirrel” C like language through browser. Electric Imp is cloud based platform, so writing code involves two sides – talking to “Agent” in cloud and then to local hardware. So it acts like a bond between two sides – Arduino talks to IMP using serial interface, which then request agent to get data from GitHub. Display is capable to display last 30 events on GitHub. Continue reading

The Diy Enigma Machine

Everyone is aware about the famous band Enigma from Germany which was formed in 1990.  This instruct able aims to build a fully functional electronica replica of the famous world German Enigma machine. The good thing, it’s able to encrypt as well as decrypt Enigma encoded messages. To implement, the LED’s a simpler but much widely used concept of multiplexing was implanted which works on the principle of persistence of vision. With the help of multiplexing,115 Led’s used only 38 pins which is still large but small when compared with the number of LED’s used. With the help of properly placed MOSFET;s and resistors, 36 push buttons used only 4 pins, and that is incredibly small. The board used to place all the boards and components was a Radio Shack 6″ x 8″ Micro Perboard is the perfect size to host all components as it provides just the right amount of space to fit everything on & will fit perfectly inside the Enigma box. After obtaining the exact dimensions of the original M4 wooden box, the next step was to… Continue reading

Humidity Controlled Fan

The project is having a really simpler name, but is extremely useful when it comes to day to day life. It’s actually a humidity controller bathroom fan which can be used in scenario where you don’t have any window in the bathroom. So even, a small shower would fill in the bathroom with steam. It features a DHT-11 humidity cum temperature sensor which works on SPI protocol a 12-V fan and a LED and of course an ATMEGA328 controller with an ARDUINO bootloader The advantage of using an ARDUINO boot loader was to provide the feature of firmware upgrade in the near future. Whenever the room humidity reaches a customizable threshold (50% by default), the device flashes the bright LED for a minute, to prompt the user to open the door of the room. After that delay, one of the two Darlington transistor boards kicks in and switches the fan on, causing the air within the room to circulate, until the humidity is restored below the threshold. The case for the device is an old bathroom perfume dispenser and it… Continue reading