Electronics-Lab.com Blog

This project shows how to build a LED circuit that is pulse fading – breathing like the “Macintosh” style LED fade off effect. The circuit is using plain electronic components like transistors, resistors and capacitors. To make LED fade on and off you just have to push a push button or trigger the input using square wave from a 555 timer IC. The producing effect is really nice. Find schematic and project details on the link below. [via]

Led throbbing – pulse fade without mcu – [Link]

With Openbiosprog-spi you are able to flash the BIOS of your PC. It is designed to be able to program any flash memory that uses the serial peripheral interconnect (SPI) which could be helpful to restore faulty firmware upgrades. Check schematics and project details on the link below.  [via]

Flash your computer BIOS with Openbiosprog-spi - [Link]

This is an excellent 50mW Hi-Fi PLL FM Stereo Transmitter that features BH1417 chip. ROHM’s new Japan has BH1417 is one of the most simple and practical integrated circuits, which combines phase-locked loop circuit, stereo encoder circuit, transmitter circuit, as well as other additions. Check schematic on the link below.

50mW BH1417 Stereo PLL FM Transmitter - [Link]

This project is a 20W audio amplifier based on LM1875 IC from National Semiconductors. With a 25V dual power supply LM1875 can deliver 20W of audio power into a 4 ohm speaker.

20W audio amplifier using LM1875 - [Link]

This project is a 3 digit – digital voltmeter based on PIC16F676. PIC is reading the analog voltage using internal 10-bits ADC and display the value on 3-digits 7-segment displays. Check project details on the link below.

3 digits Digital volt meter – [Link]

This project uses old fashioned LED displays to build a LED wristwatch that looks really cool. The heart of watch is PIC16F628A microcontroller and there is a separate oscillator to keep track of time. Check details on the link below.

LED Wristwatch - [Link]

This project shows how to build an automatic home light that will switch ON every time you are coming or leaving home. This circuit is a module to Dual Channel IR Remote Control and is separated to two PCBs. It has a dual power supply, 8.4V for IR LEDs and 5V for everything else. Ambient light level measurement is done with CdS cell on A/D converter of PIC12F675 so that the lights don’t turn on during the daytime. It also has a Sharp IS471F obstacle detection sensor with two transmitting IR LEDs, plus an additional IR focus lens for longer range. There is also a third IR LED for RC5 code transmission for “remote controller” emulation by the PIC. Check code and schematics of this project on the link below.

Automatic coming/leaving home light – [Link]

This project is able to convert low level DC signal from a pyranometer to DC current for long cable transmitting. The circuit was built with TLV2451, rail-to-rail input/output opamp made by TI. View hardware connection diagram and detailed schematic on the link below.

Pyranometer to Current Converter – [Link]

This project shows how to build a SMS remote controller. This SMS controller is able to control the power (On-Off) of 4 devices and read the status of 8 switches. It uses a GSM module and easy to find components. The heart of this controller is a ATtiny2313 and a GM-47 GSM module. SMS command execution is protected under a programmable password.

SMS remote controller V3.0 – [Link]

This project is a LAN cable tester able to check any type of LAN cables (straight or cross). Using this tool you are able to check for possible faults on LAN cables. Just connect the cable and watch the led glow one by one. If there is a faulty cable then the corresponding led won’t light. Check schematic on the link below.

LAN cable tester - [Link]