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

Infrared based Smart-board

This project is for professors who uses both a projector as well as a board simultaneously to teach. This device will help you to substitute both your boards into a single board. As the name suggest it’s controlled by infrared sensors to detect the movement of an IR led to control the remote laptop. In the whiteboard mode, the user can interact with a projected image to do things like scrolling, changing the image while in the blackboard mode the user will be able to write on a blackboard and have the IR camera trace the movements and draw it on paint and save the images The IR camera used is from the WII remote which is quite potable but still provides HD resolution and can track up to 4IR sources simultaneously. Since the camera is not available as a ready to buy unit, you will have to carefully remove it from the Wii remote. The information is transmitted with the help of RF operatred at 433 Mhz and the microcontroller is used is Atmega128p. On the laptop side, the… Continue reading

Programmer for LED Lights

LEDs have an effectiveness higher than that of just about all the customary lights and hence are used almost everywhere. The system in the article is basically a driver that can control two groups of white LED’s. The LED’s are operated in PWM mode using a suitable timing to obtain the required colour. Moreover, the entire system can be operated wireless at a frequency of 433MHz using amplitude modulation. On the receiver die, it’s a powered by a PIC16F876A which act as a decoder for the received amplitude modulated signal. The decoded signal is then processed by the controller to generate the required PWM signal for the two independent group of LED’s.  The group of LED’s are driven by using a common source transistor and therefore the design is only compatible with common-anode LED strips. Another interesting thing about the procedure is the self-learning method it uses to learn the required codes to change the level of brightness for both the warm and cold type of LED”s used in the project. The entire schematics along with the code and the… Continue reading

Universal RFToy for quick and easy interfacing Radio frequency modules

Radio modules are great for interfacing remote objects without need of wires. They are cheap and fairly easy to use. With Arduino things are even better as there are software libraries already ready for use. Rayshobby went even further. They designed a small board that incorporates Atmega328p with Arduino bootloader. 128X64 OLED display, coin cell battery, few navigation buttons and most importantly headers for plugging in various RF modules. In fact normally you would need two types of modules – nRF24L01 that comes with both receiver and transmitter, and two different four pin modules that work in 433/315Mhz frequencies. Each board works as standalone device that can be paired with other and so creating virtual wires. Few demos demonstrate how they can be used as RF recorder storing 7different signals or controlling 7 different devices. Another use is so popular wireless temperature sensor where remote sensor temperature can be displayed on receiver’s OLED display. Modules are also equipped with 3.5mm audio jack that gives ability to record and analyze RF raw RF signals wit software like Audacity. Continue reading

Hacking wireless soil moisture sensor

Most of the effort in the gardening goes to keeping plant soil moisture at right level. Human cannot always be there and check it all the time. This is why in most cases moisture sensors are used that alert when plant needs watering. You can find cheap ready made solutions that beeps when there is water needed, but also there are more complex sensors with wireless data transfer. Wireless data is gathered in to nice receiver which can be hung somewhere inside. You can get those for about $10. So Ray decided to dig in to those and see if wireless sensors can be used as generic sensors for interfacing with Arduino or Raspberry Pi. He found that Springfield 91746 Digital Soil Moisture Meter and Freeze Alert sensor communicates at popular 433MHz frequency that can be received with cheap RF 433MHzreceiver and then decoded in to real data that can be further used in your own project. Using Raspberry Pi it becomes easy to write a simple script that would log soil moisture data in to database that could be… Continue reading