Understanding Battery Balancing – is it important?

In the world of electronics, nothing is created equal. This is also applicable to batteries. A 10AH (ampere-hour) rated battery is not exactly 10AH in actual. This variation on capacity is a big problem when connecting battery in series because the battery with least capacity will be the first to full charge and full discharge. This is where you need a battery balancing circuit.

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DIY Simple Cheap Automatic Solar backup power system for 12V System

Simple version using relay board

Solar power is a renewable energy from the sun. But there are times that is raining for several days and during those days, our solar power might not be sufficient for our needs. On this project we will create an automatic solar backup power system to automatically connect to the AC grid when the battery level gets very low.

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Adafruit oled library problem Workaround

My latest project includes an OLED display with 128×64 resolution and 1.3inch size. In search for a library, I found Adafruit oled libray problem. The display does not seem to work with this library. Upon doing some research, I gave up and do this work around instead.

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Control Electric Fan with Nodemcu thru Wifi Internet Browser

Nowadays, more and more devices are being connected to internet. It allows us to smart control. On this project I will show how you can control your electric fan using an internet browser on you phone or PC. This is very simple project you can build.

This is how you will connect the relay board to the electric fan. You basically connect it to the level switch to the relay board. The color coding may not be standard and might be different on your electric fan. There are usually a wiring diagram beneath the electric fan itself. you might want to check it first.
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500W Amplifier from Eliot Sound Products

I wanted to build this project a long time ago but I have no time to do it. Today I decide to make a PCB design for it. Unfortunately I do not have any time to make the actual prototype. I will post my design so that anyone can build their own prototype.


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2SC5200 2SA1943 Simple Amplifier

If you love to build audio amplifier then you must be familiar with 2SC5200 and 2SA1943 power transistors. They are one of the most used power transistors for power audio amplifiers. While looking for a next project, I found this simple layout on the internet so I decided to make my own version with some few improvements.

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Audio Limiter Circuit

A good way to protect your speaker from overloading is by using a limiter circuit. This circuit protects your speaker by limiting the input signal to the amplifier by a certain level.

This circuit uses an IC from New Japan Radio Inc. It is NJM2761 which is specially designed for limiting audio signals. It is designed for powered speaker system to protect the speaker from overloading.

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