A few months ago, I saw an instructable by fjordcarver on how to build a coloursensor with an RGB led and an LDR. It inspired me to try whether I could improve his design. Here are the things that I wanted: The sensor should have as few pins as possible. It should work as a […]
Build your own (at)tiny colour sensor. Read More »
Properly maintained rechargeable batteries can provide good service and long life. Maintenance involves regular monitoring of battery voltage. The circuit in Figure 1 works in most rechargeable batteries. It comprises a reference LED, LEDREF, which operates at a constant current of 1 mA and provides reference light of constant intensity regardless of battery voltage. It
Simple battery-status indicator uses two LEDs Read More »
Aurora 48 is capable of individually controlling 48 Full color LEDs using a 40 pin microcontroller. The principle of operation is based on my other “Aurora”s. (see Aurora 9×18) The circuit is relatively simple and straightforward. If you’ve seen other LED matrix type circuit, this should look familier. In a nutshell, the 48 RGB LEDs are divided in two
Aurora 48 – 48 RGB LED Sequencer Read More »
I am in the process of designing a function generator and I needed a frequency counter to check it against. This project uses a minimal number of components for a very economical and compact design. A bare-bones Arduino clone is at the heart of this project and the measured frequency is shown on an LCD
This article looks at the options for getting started with a GPS design for industrial applications, from the transceivers to modules and the evaluation boards available, as well as the antenna issues to consider. It looks at how modules from suppliers such as Antenova and NXP Semiconductors can be used, extending to single chip implementations
Getting Started with GPS Read More »
I love robots. Normally the ones I build are quite large and wouldn’t fit in your pocket, but for a change of pace I decided I would try something small and fun! This robot is exactly that, and in fact fits inside of an altoids tin. It is inexpensive, versatile (so many different sensors can
Tiny Altoid Tin Robot With Personality Read More »
A circuit that properly charges sealed lead-acid batteries ensures long, trouble-free service. Fig 1 is one such circuit; it provides the correct temperature-compensated charge voltage for batteries having from one to as many as 12 cells, regardless of the number of cells being charged. The Fig 1 circuit furnishes an initial charging voltage of 2.5V
Charger extends lead-acid-battery life Read More »
Switching DC/DC voltage converters are popular because they provide efficient power conversion that can exceed 90 percent. That is an advantage both when input power is at a premium and when it is difficult to get the heat out (common challenges for engineers designing compact portable products). With key power component manufacturers offering products that
Selecting the Right Voltage Converter Is Not Just About Peak Efficiency Read More »
This is a open source project of RC Car with control from Android Phone via Bluetooth. The controller is used with .NET Micro Framework: FEZ Panda II, but you may use any controller works with .NET Micro Framework core (Netduino, GHI Electronics board’s and other). All source code is available at GitHub. To control the machine
CxemCAR 1 – Android Control RC Car over Bluetooth Read More »
Thalamus is a small board containing a USB-capable 32-bit 72MHz ARM Cortex-M3 microcontroller, 3-axis accelerometer, 3-axis gyroscope, 3-axis magnetometer and barometer. Thalamus started out life as a flight controller for the R10 Quadrotor systems, providing stabilization at 400Hz. However, packing a fast microcontroller with native USB capabilities, and with two SPI ports for communications, Thalamus
Thalamus IMU – Motion sense/control board for your projects Read More »
