My Light Diagram

It looks like the iPhone 5 wasn't Apple's last big debut in 2012. Apple just sent out invitations to a special event that it's holding next Tuesday, October 23, starting at 10 a.m. PT, presumably to unveil the much-rumored smaller iPad model and a 13 inch MacBook Pro with Retina Display. The tagline of the invite is "We've got a little more to show you," and the invitation shows the top of Apple's logo. Apple is holding the event at the California Theatre in San Jose, Calif., just a block away from the courtroom where its major trial with Samsung took place. The invitation confirms a report from AllThingsDigital last week, which claimed the event date would be October 23.  Since before its very first model of the iPad came out, Apple has been rumored to be working on a smaller version. But expectations that the company would double down on its iPad line have increased, especially after competitors like Amazon and Google began to put out smaller tablets th...

Only a few years ago, the choice of LEDs was limited to IR, red, yellow, and green. The LED manufacturers have been busy extending the spectrum, and filling in the gaps. The latest generation of organic LEDs (OLEDs) has added some dazzling new colors to the spectrum. This circuit uses a set of 13 differently colored LEDs to generate a full color spectrum. The photo does not fully represent the colors generated due to camera limitations. The real-world display is very eye-catching. If you want to "trick out" your PC, this circuit is for you. Forget about those boring blue PC light displays. 13 Color LED Rainbow Circuit Diagram: Specifications: Operating Voltage: 6-12V DC Operating Current: 145ma at 12V DC Theory: The LM2940T-5.0 low dropout voltage regulator converts the 6-12V DC input power to regulated 5 Volts. It was chosen over a standard 7805 regulator so that the circuit could maintain regulation while operating on a 6V battery. The 1N4001 diode protects the circuit from...

This PSU has been especially designed for current-hungry ham radio transceivers. It delivers safely around 20Amps at 13.8V. For lower currents, a separate current limiting output, capable of 15ma up to a total of 20A has been added. Let us see what we have got here. The power transformer should be capable to deliver at least 25A at 17.5 to 20V. The lower the voltage, the lower power dissipation. The rectified current will be “ironed” by the C1, whose capacity should not be less than 40.000uF, (a golden rule of around 2000uF/A), but we recommend up to 50.000uF. This capacity can be built up by several smaller capacitors in parallel. The base of this design is a simple 12V regulator (7812). The output voltage can be brought to desired value (here 13.8V) by two external resistors (R5 and R6) using this formula: U= 12(1+R5/R6) The low currents (here 15mA) will keep the 7812 in its regular function. As soon as the current rises over 15ma, the voltage drop on R4 will “open” the Q3,...