Arduino illuminated sign

Nowadays led signs and banners are getting more and more popular, also their price is going down slowly, but personalized ones still have a spicy price, so I`ve decided to make one by myself for less than 30$.

I wanted to lit up every character separate in order to make it look more interesting and professional, so I had to use a cheap and small Arduino Nano board.

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Rewinding a microwave oven transformer (MOT) for general purpose use

Introduction

In this article I am going to present my struggling about rewinding a microwave oven transformer (MOT) in order to make a low voltage (20-30V) but high current (15-30A) transformer. I have done these experiments in order to make a cheap but a very handy transformer for a bench supply. These types of transformers 500-100 VA transformers cost hundreds of USD where I live, but these microwave oven transformers can be purchased for a few dollars used, because they can be only used for special applications (like where it comes from, microwaves). They usually get shorted or interrupted on the secondary winding due to the high voltage, poor insulation, thin aluminium cross section wire. Many times the primary winding remains intact.

Before starting with the practical work, we have to settle a few theoretical consideration, and proving them in small scale.

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