TECH KEEDA

4017 DECADE COUNTER 4017 is an integrated circuit which has been designed to count pulses.  It has 16 pins and looks like any other 16 pin integrated circuit. To understand well let look into the pin connections of 4017 decade counter. 1. Pin connections:                               The 4017  decade counter has ten outputs which go HIGH in sequence when a source of pulses is connected to the CLOCK input and when suitable logic levels are applied to the RESET and ENABLE inputs. There are 10 output pins present in this decade counter. Vss for 3 - 15 volts is given at  pin 8 . Ground is connected at pin 16 . Clock  pulses are provided to  pin 14 . RESET is connected on pin 15 . 2. Now what is a decade counter and how does it work? The counting action of decade counter can be well understood from the graph below.  Just one of the individual outputs is HIGH at a time. This is quite different from the behavior of a BCD counter like the  45

TITLE: Sound operated music bell CIRCUIT DIAGRAM: COMPONENTS LIST: Resistors (all ¼-watt, ± 5% Carbon) R 1  = 10 KΩ R 2  = 470 KΩ R 3  = 2.2 KΩ R 4  = 150 KΩ R 5  = 100 Ω VR 1  = 1 MΩ Capacitors C 1  = 22 µF/16V C 2  = 0.1 µF C 3  = 0.22 µF C 4  = 220 µF/10V C 5  = 0.01 µF Semiconductors IC 1  = NE555 IC 2  = UM66 T 1  = BC548B T 2  = SL100 D 1  = 1N4001 Miscellaneous MIC 1  = Condensers microphone 34 LOD SW 1  = On/Off switch DESCRIPTION: This is the simple project in which you can turn on door bell just by snapping your fingers. In this circuit the use of external relay is eliminated. The circuit comprises of trigger stage (around T1 - BC548B ), a timer stage (NE555), and melody stage (around um66 and sl100).Transistor BC548 is biased in class coperation.Every second sound cause triggering of pin 2 of NE555 ic.When VR1 is at maximum, the hold-on time ofNE555 is arouund 30 seconds. APPLICATIONS: Turn on lights of your study room

TITLE: Bluetooth enabled mobile controlled robot CIRCUIT DIAGRAM: COMPONENTS LIST: Battery 12v. Wires for connection. DTMF IC cm8870 or mt8870 Motor driver ic L293D Bluetooth headset A mobile phone with bluetooth facility in it. 7805 voltage regulator ic DESCRIPTION: This is a simple mobile controlled robot project. In this project user can control robots just by specific set of keys. First Bluetooth enabled phone is connected to Bluetooth headset like normally its done. When key on mobile is pressed then according to following table different frequency is generated by phone. 1209 Hz 1336Hz 1477Hz 1633 Hz 697 Hz 1 2 3 A 770 Hz 4 5 6 B 852 Hz 7 8 9 C 941 Hz * 0 # D These are also called as DTMF tones which are heard / received by bluetooth headphones. These tones are then passed to DTM

Title : Fire alert systems for homes, hospitals, other buildings. Circuit Diagram:   Component list: 1 Photo interrupter module 2.Speaker  8 ohms 1 w Ic 555 Capacitor c1 – 0.04 uf , c2 0.01 uf,  c3 100 uf 25 v Resistor r1 = 470 ohms,r2 = 4.7k, r3 = 1k ,r4 = 47k Variable resistor vr1 1k. Battery 9v. Wires for connection Description: This is a simple fire alert project. This project activates alarm when smoke is detected. Here smoke is detected by photo interrupter module (at bottom left of circuit). The photo interrupter module consists of an LED and a Photo transistor. The light coming from the led falls directly on the photo transistor, this makes the collector terminal to go ground potential and activates the reset control of 555 timer. If there is an interrupt on the path of LED and Photo transistor such as smoke, the light does not reach the photo-transistor, causing the collector voltage approximately equal to supply

Title: AUTOMATIC PLANT IRRIGATION SYSTEM Circuit:        [  Note: If circuit diagram is not clear then you may zoom using ctrl and '+' .] COMPONENTS : Capacitor (C4) = 10u 16V. Capacitor (C5) = 0.01u. Resistor (R3) = 27K Resistor (R4) = 27K Diode (D1 and D2) = IN4148 Relay = 6V, 150 ohms DESCRIPTION :                Imagine if plants are watered automatically and regularly. One does not need to look into it always .Just turn on this system and its done.                Circuit is simple. Soil has high resistance when it is dry and has very low resistance when it is wet. We insert two probes in the soil in such a way that that they will conduct when the soil is wet and they will not conduct when the soil is dry. So, when the probes do not conduct, system will automatically detect this condition, and can start watering plants. Now how exactly it does that ? Circuit Description:            Two probes which are connected to the circuit a

1. Simple Hello world example #include<stdio.h> //  to include library "stdio.h"  int main()                    //  every c program starts with main function {  printf("Hello World"); //  printf() function prints whatever is placed within ' "  " '  return 0; } Output : Hello World Description: 1.First line "#include<stdio.h>" indicates that we want to use stdio.h library in our code. 2.int main() - all code is written in this block. "int" return type is integer. 3.printf("Hello World"); - to write a "hello world" message on console How to run and execute:  Step 1 : Type this code in your turbo c compiler and save it with appropriate file name (ex: helloWorld.c). Step 2 :Click compile -> compile Step 3 :Click run ->run Step 4 :Press alt+x to exit from turbo C and see the output. Step 5 :To continue with your code type "tc" again. In marathi lan

Simple example on how "for loop" works. Syntax: for( initialisation ; condition ; incrementation or decrementation)  {  } Initialisation  - Initialise any value Condition - Basically its till when the loop should continue. (Ex: number < 10) incrementation or decrementation : To increment or decrement any value. Example to print 10 even numbers. #include<stdio.h> int main() { int num; for(num=0;num<10;num++) //Repeat this block  {          if(num%2 == 0)          {             printf(" %d ",num);          } } return 0; } Output: 0 2 4 6 8 Description: In this example is same as while loop.We first repeat some block of statements till the value of "num" variable reaches to 10.Then we check if the current number is even and print it. for(num=0;num<10;num++) { }- this statement  first assigns zero value to num. Step 1:Then condition is checked.Pointer then enters the for loop block if condition is true / satisfied. Step 2:It then executes

In order to install Turbo C (Which can be found  here  )in windows 7 you first need to download and install dosbox  here . Step 1:  Create a folder in c:\ drive and name it turbo (or anything convenient for you) Step 2:  Now extract TC installer in this newly created folder Step 3:  Run dosbox from start menu.This will load dosbox emulator. The prompt will display Z:\> Step 4:  Now you need to mount the folder that you created in the previous step. in the prompt type: Z:\>mount c c:\turbo You will get a message that drive c is mounted as local directory c:\turbo. Step 5:  Now just by few commands you can open your turbo c Just type: Z:\> c: c:\> cd tc/bin c:\tc/bin:> tc Step 4:  Turbo c will start .Go to Options > Directories. Change all the drives to c if not already there. Example: In include Directories H:\ TC\ INCLUDE Simply replace 'H' with 'c' Similarly for other options below it. Configure DosBox