FM Radio with Frequency Display

A simple FM radio with a display that shows the frequency and audio amplifier. My goal was to make simple FM radio with a display that shows the frequency. And manual control over frequency and volume. 2. Hardware You can use Arduino Uno or Nano: 2.1 RDA5807 The main component is RDA5807 Sinle-Chip FM Receiver Module. It’s […]

ATtiny13 “Candle” Flickering Lamp

The theory To achieve random variation of LEDs behavior, like candle flicker, we need to generate random numbers. Embedded systems (like ATtiny13) generally use some hardware based pseudo-random number generators like linear feedback shift registers (LFSRs). This code is use 32-bit Galois LFSR (Linear-feedback shift register) random number generator. The bit positions that affect the next state are called the taps (32, 31, […]

Electromagnetic Field (EMF) Amplifier

Electromagnetic Field (EMF) is all around us, but we do not see or hear them. By amplifying it we can make it be heard. The theory Source: Electromagnetic fields of all frequencies represent one of the most common and fastest growing environmental influences. All populations are now exposed to varying degrees of EMF, and the […]

Light with Solar Charged Battery

Light with Solar Charged Battery

Stopwatch with ATtiny13 and TM1637 LED Module

Full code on GitHub: If you have 5v power source you do not need to build the LM7805 Voltage regulator circuit as in the drawing. Code Download TM1637 Library: put files in same folder with code. Arduino code: That how long is 1 second may need manual calibration. For now it is 90m/s. _delay_ms(90); // […]

Selfmade i2c 7-segments display with ATtiny85

0. Intro Because I had a bunch of common anode 7 segment displays i decided learn how to make i2c slave device. 1. 7-segment LEDs My 7-segment LEDs are marked as 5611BH and looks like this: 2. 7-segment LEDs module I connected four 7-segment displays together on PCB and i added resistors (470Ω). 3. Shift […]

Self Drive Piezo Buzzer

Why do some piezo elements have three wires? Most piezos have two connections, but this type has three. They are called self drive types, and they’re meant to be used as part of the oscillator. The piezo effect works both ways: if you apply a voltage the piezo stretches, but also if it stretches it creates a […]

Radio Frequency Transmitter & Receiver Module with Arduino

Starting point how to use wireless radio frequency transmitter & receiver modules. 1. Download RadioHead library: Unzip and copy it into Arduino library folder: Now you should to see RadioHead example code: 2. Transmitter module: Antenna lenght depens do you have 315, 330 or 433 MHz module. Best is to use the antenna of 1/4 wavelength (or […]


Klimberdaja is audio visual music generator and player. Like a simple automated piano or something like that. I wanted to learn how Shift Registers work and then I did it. Arduino Code: // const int volumePin = 7; //Pin connected to latch pin (ST_CP) of 74HC595 const int latchPin = 8; //Pin connected to clock […]