LM317T Voltage Regulator with Pass Transistor

I am showing a method of using a CdS photoresistor to control a standard triac dimmer circuit that is wired to an electric drill motor (a universal motor). The CdS photoresistor is driven by an LED that is controlled by a PWM pin on an arduino microcontroller. This system provides a very easy way to control 120V AC devices with a single PWM pin, and not use any timing code or method to detect the zero-crossing of the AC power since this is done intrinsically in the circuit. It also offers true electrical isolation between the AC line voltage and microcontroller.



http://www.youtube.com/watch?v=7yEABsNyRfo&hl=en

Petey demos his home made pedal power supply brick . the unit can power a pedal board @ 9 volts , negative polarity , meaning center conductor is the minus , like boss standard . it has two 12 volt ports on for reverse and one forward polarity . additionally featuring ports for 3 , 5 , and 6 volt outputs for powering smaller draw devices . the unit is fused , uses an led and is powered from an old HP printer power supply that puts out 18 volts / 1.6 amps . simple design featuring filtering , and uses commonly available / low cost lm7809 and other voltage regulators . AC adapter repair video : youtu.be



http://www.youtube.com/watch?v=MtiZRGfSGBI&hl=en

Got a CRT TV with a power supply failure that is too complicated or expensive to repair? Get one of these one-size-fits-all Universal TV PSUs. They provide the necessary voltages to power up all of the TV's internal circuits, just disable the original PSU, wire the replacement in and find some place inside the set to hold the board in place. Your TV will come back to life! In this video I show you how I got a 21" Panasonic that survived last year's 8.8 earthquake back to life with one of these universal supplies. The switching transformer was cracked making repair a complicated and expensive affair. Fitting the universal PSU to replace the main B+ supply got it working and saved me quite a bit of money and headaches! I got this particular model locally from www.cm2.cl Here's the very same one from an online distributor tinyurl.com



http://www.youtube.com/watch?v=rh21GpGPFSM&hl=en