3000mAh SIMPLE POWER BANK

Hai…..friends. This is my second project…Have you ever used a readymade power bank? Hope yes! It’s very useful to new generation, especially during long trips. Its very easy to make it. There is nothing special in a power bank. It

Simple Preamplifier

This is a very simple, cheap preamplifier which can be used for condenser microphone.Or it a can also be used as a simple low power audio amplifier………this amplifier can be prepaired by 2n3904 transistor which is very very cheap and