Electronics-Lab.com Blog

The Glowies use a small microcontroller, but they are really quite simple in both parts and function. The core of the unit is a silicon diode used as a temperature sensor (actually, two of them). These Glowies sense when temperature drops, and it turns blue. If the temperature rises, it turns red. Plus, it’s completely solar powered, so you never have to change the battery. And I used very inexpensive parts, so you can’t get much cheaper!

Temperature-sensitive LED Glowies - [Link]

BoxMaker is a little Java application that can generate the outlines for a box to be out of some material with a cutting device (ideally using wood/acrylic on a lasercutter!). You tell it the dimensions of the box (width, height, depth, material width), and it generates a PostScript file with the outlines for the 6 sides of the box. The dimensions are the outside lengths of the box. [via]

BoxMaker makes any size box template - [Link]

This is wireless FM transmitter project, when you speak into the transmitter and others hear you on any FM radio. The transmitter can be built in an afternoon with simple, affordable and widely available parts. Construction is fun and much can be learned although performance is modest; for example, your voice gets difficult to hear at distances greater than 25 feet. [via]

Wireless FM Transmitter - [Link]

The triac lighting-control circuit in Figure 1 is small and inexpensive because load and housekeeping power come directly from the line voltage, thereby eliminating bulky, expensive supplies. The CLZD010 closed-loop controller maintains constant light intensity by automatically adjusting the timing of the triac’s firing until the feedback signal and setpoint command are equal. [via]

Triac light control - [Link]

A high speed A/D converter (TLC5510) drives the USB module directly.Maximum clock rate is about 1MHz resulting in bandwidth limit of about 500KHz. The sampling rate may not be very exciting for RF people, but can be perfectly acceptable for audio and teaching work. [via]

Simple USB oscilloscope for the PC - [Link]

The circuit uses a serial-in-parallel out shift register, 74HC595 for receiving serial data from uController board. See example of U5 in the schematic, SER is for data input, SRCLK is shift clock and RCLK is Latch clock. Each data bit is shifted into the register on rising edge of the shift clock. When all data bits are shifted into the 8-bit register, the rising edge of RCLK will clock the data to be latched at each output bit. [via]

SPI Interface Big 7-Segment LED - [Link]

Seb Lee-Delisle made this cool particle system using an Arduino board and an 8×8 LED array. He writes:

The only real trick here is that I’m working internally with a much higher resolution that the actual 8×8 grid, and then rounding to the nearest pixel when displaying each particle. This gives a really smooth movement. I’m only actually lighting one LED per particle but due to the Persistence of Vision (POV) effect it looks like there are more. [via]

Arduino particle system - [Link]

CodeLock is an AVR based electronic combination lock it is realised with Atmel AVR microcontroller AT90S2313 or ATtiny2313.This project used for access control. Program in hex code is 2 kB long. User code is consisted of 1 to 4 digits. If you buy the chip than user code is consisted of 1 to 8 digits. If the code is entered in the correct sequence, then after 1 second the relay and the electric striker (in the door) switch on for 1 second and then switch off again. User code can be changed via 3×4 matrix keypad. [via]

AVR tiny code lock - [Link]

This project like others capacitance meter that use charging time measurement technique (τ=RC). Circuit is really simple. There are three buttons used. Two of them are used to calibrate capacitance meter in order to remove stray capacitance. Third button is used to save calibration data to EEPROM memory. You can download assembly source code compile and burn to PIC16F873A microcontroller. I guess this is a nice tool that fits in to collection. [via]

Auto-range capacitance meter - [Link]

GoldPic 3 Pulse Induction Metal Detector Features :Fast Response Non-Motion All-Metal Silent Search Mode ,digital processing of the detection signal ,sensitive Analog / Digital Converter ,push Button Threshold Zeroing ,microprocessor Controlled ,liquid Crystal Display ,easy to build & use. [via]

GoldPic 3 Pulse Induction Metal Detector - [Link]