Sajee tronics

Hi,I recently designed a sort of "library" in order to make easier to play exact notes on arduino with the buzzer. I included the frequencies of the notes (pleasant to be heard) with #defines . I then defined the value of the BPM ( you can modify it obviously) and according to that I defined the note values ( the most commonly used ones). With this defines you can easyly play a note with the command "tone" like this: tone(pin, note, duration) Code : /* Play Melody  * -----------  *  * Program to play melodies stored in an array, it requires to know  * about timing issues and about how to play tones.  *  * The calculation of the tones is made following the mathematical  * operation:  *  *       timeHigh = 1/(2 * toneFrequency) = period / 2  *  * where the different tones are described as in the table:  *  * note         frequency       period  PW (timeHigh)     * c            261 Hz          3830    1915      * d            29

Arduino Remote Trigger for DSLR How to make this kind of shots ? Boys "Ale Ale song" Anniyan -Fight scene. Multiple DSLR's controlled by a timely trigger system. - "Time Slice" Camera Set up for the fight scene We will see a small example to trigger one camera . But to take this kind of shots u can use this same module by having different relays for each camera. I have a Canon DSLR camera which uses a 2.5mm stereo phono jack connector to allow for a tethered remote.  These are surprisingly expensive.   http://www.doc-diy.net  provides an illustration of the way the connector works.  It is pretty simple to put some electronics behind your camera for stop motion or candid photography.   It controls the camera to automatically take a photograph within a period of 0-60 seconds or 0-60 minutes, set by a sliding potentiometer.  I can enable or disa

If you've ever dreamed of having a spectacular reef aquarium in your home, but think you lack the time, funds, or knowledge required, think again! Creating a beautiful reef ecosystem does not have to be complicated. The following five easy steps will help simplify the process. In a period of just 12 weeks, you too can enjoy the colorful beauty of a home reef aquarium for many years. Suggested Water Chemistry Values pH 8.2-8.4 ammonia 0.0 ppm nitrite 0.0 ppm nitrate < 40.0 ppm (the lower the better) phosphate < 0.2 ppm (the lower the better) temperature 74-78oF specific gravity 1.022-25 alkalinity (dKH) 2.3 meq/L or 8 dKH calcium ion 380-450 mg/L Maintaining Your Reef Ecosystem Monitor and test water parameters regularly to provide a healthy marine environment. Perform 25% water changes at least once a month and perform regular filter maintenance. Feed thawed small amounts of frozen food, twice daily. The fish should be able to finish the given porti

I have been playing around with a 434MHz RF Transmitter and 434MHz RF Receiver from Sparkfun so that I can transmit and receive RF signals between two Arduino micro controllers. After a couple of unsuccessful attempts using the tutorials from the product page, I finally managed got the equipment to work using the transmitter.pde and receiver.pde code from the Arduino Library. I modified the receiver code to receive ASCII intend of HEX responses from the receiver. The equipment I needed: 1 Arduino Uno R3 1 Arduino Duemilanove 1 RWS-371-6 Wireless Hi Sensitivity Receiver Module (434MHz) 1 TWS-BS Wireless Hi Power Transmitter Module (434MHz) 1 Breadboard 11 Wires 2 USB cables to connect to the Arduinos I experimented with some different configurations but I managed to get results connecting the transmitter to the 3.3V or 5V power supply and connecting the data lead to pin 12 on the Arduino. The receiver could only be connected to the 5V power supply and the data lead