This tutorial will guide you when building your own single transistor tesla coil. We’re all fascinated by the sound produced when high voltage is discharged so sooner or later you’re gonna want to build it. Apparently using a single transistor it’s better and the whole thing works better.
This is a simple do-it-yourself (DIY) headphone amplifier project that is fashioned primarily after the Class A MOSFET Headphone Driver project by Greg Szekeres and to some extent Mark’s DIY Class A 2SK1058 MOSFET Amplifier Project. The amplifier concept is simple and follows a typical single-ended class A circuit utilizing an active constant current source (CCS) in place of a passive resistor. A CCS doubles the efficiency of the circuit over that where a passive load resistor is used, bringing it to a maximum of 25%.
Class A Headphone Amplifier Boost Your Sound: [Link] - [via]
In this project there are actually 3 chargers combined in a single PCB, each charger having an output voltage of 4.2V. You can cascade them to become charger fit for 2 or 3 cels Lipo pack. The transformer used is 3 x 8 VAC. As more and more devices are powered with LiPo batteries such a charger could come handy some day.
DIY LiPo Charger: [Link]
You all know that opto osolator boards are used to pass signal between circuits without connecting them electrically. They are great for eliminating noise problems, or to connect circuits that have different voltages.
The opto isolator is very easy to use. Since it just passes signals through it, you just hook it up between the two different devices you want to communicate. Additionally, you will need to properly hook it up to each devices power supply. The device is intended to isolate the circuits electrically, so each side needs to be powered independently.
T-Clock is a demo-application for Philips LPC2000 ARM7TDMI controller with a KS0108/KS0107-based graphics-LCD (128*64 pixels), DCF77 time-receiver and one wire bus (for DS18×20-Temp.-Sensor).
The time and date are received with a DCF77-receiver-module. The DCF77-signal is transmitted from a station near Frankfurt/Main, Germany and can be received all over Europe, North Africa and the Middle-East. Please visit www.ptb.de and ask google with “DCF77″ for more information. In times when the DCF77-signal is not available (i.e. thunder and lightning near transmitter) the RTC of the LPC-controller is used to drive the clock.
The clock also display the temperature measured trough a DS18×20 family sensor. he sensors provide the temperature in digital form on a One-Wire-Bus. The Maxim Web-Site has a lot of information on the One-Wire-Bus.
The whole project should cost you about 100 Euro’s, not cheap but a very good and interesting project for ARM microcontrollers.
T-Clock An ARM7 Controlled Blue LCD Clock: [Link]
