RAIN ALARM by Hankumar

This is a simple circuit that can be used to detect rain. It will give a loud beep when the first drop of rail falls on the sensor. So it useful to detect rain where sun drying is carried out.Op-Amp IC 741 is designed as a voltage comparator. Its inverting input pin2 receives half supply voltage (4.5V) through the potential divider R1 and R2. Its non-inverting input pin 3 is connected to touch pads and variable resistor VR1. Output of the comparator becomes high only when its pin3 gets a higher voltage than pin2. Normally pin 3 is low because it is not getting current from the positive supply. So output remains low. This inhibits transistor...

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POWER SUPPLAY DIRECT FROM MAIN

This circuit can supply voltage about 12V 15mA directly from main AC . The modification for other output voltage can replace the zener diode. careful of hot main.This circuit from topsitusc...

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How to Learn Holly Quran + Sound Of Its Portable

The simple learning qur'an with arabic text and pronounce sound just install Holly quran and murotal mp3 at the same gadget like Nokia 5630. They can running on same time on Symbian OS. Fisrt open Holly quarn/mushaf and then play mp3 murotal at same ju...

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Troubleshooting laptop keyboard typing random

Troubleshooting laptop keyboard typing random, turns a small problem, not a virus and others. The problem is the Fn + NumLk active, then turn it off by pressing Fn + NumLk again .... the problem is resolve...

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Programming (Interface) LCDs with AVR Microcontroller ATMEGA8535

Basic Theory of LCDLCD (Liquid Crystal Display) is a viewer module which is widely used because it looks interesting. LCDs are the most widely used today is to refurbish M1632 LCD because the price is quite cheap. M1632 LCD display is an LCD module with 2x16 (2 rows x 16 columns) with low power consumption. The module is equipped with a microcontroller specifically designed to control the LCD.Artificial Hitachi HD44780 microcontroller that serves as the LCD controller has CGROM (Character Generator Read Only Memory), CGRAM (Character Generator Random Access Memory), and DDRAM (Display Data Random Access Memory).LCDs are common, there is a length...

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SERIAL to USB Home Made Using ATmega8

 [ BROKEN LINK DOWNLOAD WAS UPDATE] the other choice build your own USB to Serial whitout microcontroller clik THIS  In the following article will discuss how to implement and make a USB to Serial Converter own with ATmega8 microcontroller. In this ATmega8 will be given free firmware source code and can be downloaded at the bottom. Because the ATmega8 there is no facility for communication with the USB, then inevitably the data with the USB communication protocol must be made on the firmware itself. For a study guide the USB protocol can be seen in other parts of this website or click the link below to view it. In the firmware...

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Straight and Cross Cable LAN

To connect two computers or connecting two HUB / switch with UTP cable, can use a crossover cable. If mo connect computers to the HUB / switch, use straight cables. more ...In straight and cross wiring, we can see standards set for this wiring problem, EIA / TIA 568A and EIA / TIA 568B.EIA / TIA 568A EIA / TIA 568BStraight CableStraight cable is a term for a cable that uses the same standards on both ends of its wires, could EIA / TIA 568A or EIA / TIA 568B on both ends of the cable. Simply put, the sequence of colors on both ends of the same. In straight cables, pin 1 at one end of the cable connected to pin 1 on the other end, pin 2 connected...

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