This project is made by Håkon A. Hjortland. The idea is pretty simple and original. He used rotating mirrors to create a video projection. 16 differently tilted mirrors were fixed on a round drum that spins at about 20 – 30 s-1. Each mirror draw a separate line on a screen. For each pixel, the [...]

The generator was build and tested by nuxie1 using XR-2206 function generator IC, which is capable to generate sine, square, ramp and pulse waveforms in frequency range of 0.01Hz to 1MHz. The amplitude and frequency is modulated by voltage (potentiometers). The example circuit from datasheet worked well:

Second step – project creation. Project Eagle files [...]

Sometimes you need quick an easy solution for programming serial EEPROM memory chips. I think easiest and well known method is to use simple programmer adapter with very few components:

This adapter is connected to RS232 port and there is no need for additional power supply as it comes form PORT pin. Adapter is compatible with [...]

I heard about this method an decided to try with may board. I needed to replace Atmega128 chip, but didn’t have hot air solder for desoldering IC. I tried this weird desoldering technique and I can say, that I satisfied. Tracks and other parts were saved.
Watch a video:

WPvideo 1.10

Atmega128 desolder using simple lighter.
Download!

Now my Atmega128 [...]

I found interesting article about capacitance of ceramic capacitors may depend on voltage applied.
It seems to be that in some designs you can face a problem when ceramic capacitor capacitance may strongly depend on voltage. Few tests were done with various capacitors using following circuit:

In the circuit CX – tested capacitor; C0 – known [...]

Building AVR Jtag clone
Finally I found some time to finish AVRJTAG clone. It was hanging for a while on a breadboard with bunch of wires. I have made an Eagle CAD project with PCB layout you will find at the bottom of article.

 
I didn’t change the circuit very much from previous, just added ISP header(but [...]

Dear website visitors. As you may noticed the site were experiencing technical problems. Due to hosting server instability I decided to move it to another physical server. Hope to get thing better. After moving it seems to be working fine. Thank you for you patience and have pleasant browsing.

Decibel is a special unit that is a little different from other measuring units in everyday practices. This is non physical unit but more mathematical understanding. Decibel (dB) units are similar to percent (%), just different calculation and purpose. As a percent units so decibels are used to compare two quantities. As whole value in [...]

Regular ad hoc filters don’t guarantee optimal signal filtering as there is no any criteria that evaluates filter characteristics. Usually filter parameters are calculated empirically and filtering is done by best results.
In order to avoid such shortage there are optimal filters used where parameters are optimized by some criteria. The main idea of optimal filtering [...]