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Building a Fun and Smart Home with a DIY Smart Doorbell

  Title: Building a Fun and Smart Home with a DIY Smart Doorbell Introduction: In the exciting world of electronics, there's nothing quite as thrilling as creating your very own smart home gadgets. Today, we'll embark on a journey to build a Smart Doorbell using simple and easily accessible equipment like the Arduino Uno, an IR proximity sensor, and a buzzer. This DIY project is not only a fantastic introduction to electronics but also a step towards transforming your home into a tech-savvy haven. So, gear up, young inventors, as we venture into the world of smart homes! Materials You'll Need: 1. Arduino Uno: The brain of our smart doorbell, capable of processing information and controlling the connected devices. 2. IR Proximity Sensor: A nifty gadget that detects the presence of objects in its vicinity. 3. Buzzer: This component will be the voice of our smart doorbell, alerting you when someone approaches. Step 1: Setting Up the Arduino Uno: Begin by connecting your Arduin...

Resistor and their colour code

Standard Resistor Values and Color 

resistor color code are as follows


The colors brown, red, green, blue, and violet are used as tolerance codes on 5-band resistors only. All 5-band resistors use a colored tolerance band. The blank (20%) “band” is only used with the “4-band” code (3 colored bands + a blank “band”).

Example #1



A resistor colored Yellow-Violet-Orange-Gold would be 47 kΩ with a tolerance of +/- 5%.

Example #2



A resistor colored Green-Red-Gold-Silver would be 5.2 Ω with a tolerance of +/- 10%.

Example #3



A resistor colored White-Violet-Black would be 97 Ω with a tolerance of +/- 20%. When you see only three color bands on a resistor, you know that it is actually a 4-band code with a blank (20%) tolerance band.

Example #4



A resistor colored Orange-Orange-Black-Brown-Violet would be 3.3 kΩ with a tolerance of +/- 0.1%.

Example #5



A resistor colored Brown-Green-Grey-Silver-Red would be 1.58 Ω with a tolerance of +/- 2%.

Example #6



A resistor colored Blue-Brown-Green-Silver-Blue would be 6.15 Ω with a tolerance of +/- 0.25%.

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