Resistor color code

A resistor is the most important electrical component in almost every electronic circuit, it can limit current to any load such as led, transistor, opamp, etc. We must read resistor color code if we want to know the resistive value, tolerance, temperature coefficient. Resistors have different color bands (3,4,5,6) the more color bands the more resistor's information.Now let's start with 3 bands resistor color code.

The above resistor has only 3 bands First digit, Second digit, and multiply. A 3 bands resistor color code has fixed +/-20% tolerance that means if color code value is 1,000 ohms the real life resistive value may be +/- 200 ohms. 
4 band resistor color code

A 4 bands resistor color code has tolerance value color strip, the resistor on an above picture has 5% tolerance. This type of resistor uses in a regular circuit such as television,radio,washing machine.

5 bands resistor color code

A 5 bands resistor color codes have third digit color bands.
1(first digit) 0(second dig…

How to remove scratch coating from mobile phone camera

Now a day a mobile phone camera lens cover coating with anti-glare, scratch resistance. However, every coating material can be scratched easily even the smartphone camera coating with scratch resistance material, and it makes the camera quality drop significantly. 

The best way to fix this problem is removing the scratches coating off the camera lens cover, but you need to remove it the right way or you may end up make more scratches to the camera lens cover.

My instruction is easy to do and make a pleasant result. All tool you need is old sim card adapter and car polishing(no rubbing bead type)

You may have a question in your mind that why I use sim card adapter as the rubbing tool.
- The simple answer is a sim card adapter made of plastic that softer than commercial cell phone camera lens cover.

Please check the video below for the instruction and before and after comparison.


  1. Replies
    1. Some toothpaste has micro bead that make scratch even worse.


Post a Comment