Trick-filled LED Fader to spice up the beat

Wilfred came up with a very flashy idea to spice up a Dutch carnival snare drum, instead of flashing random colors from high powered RGB LEDs he decided to make the LEDs fade along with the beating of the drum. Using an AT90S2313 microcontroller to induce the lighting patters and a piezo sounder as a microphone Wilfred gave a whole new life to the monotone snare. When the drum is hit, Pin3 of the MCu is pulled down through a Darlington pair, starting the fader’s sequence of flashes and fades. Alternate color patterns were use to give more emphasis to the fading transition plus giving a dancing light effect. If the hitting halts a heart beat sequence will automatically start after 20 seconds. Firmware for the MCU was written in BASCOM, for those of you who can’t compile in BASCOM Wilfred also provided the .hex file. Schematics can be found here while a new untested board layout, in eagle cad is also available. Cheers! Drum lights just turned the Dutch carnival to a lively light-filled festivity. Continue reading

This RDS Decoder Project Will Light Up Your Day!

You’re always wanted to build a RDS decoder, but you’re afraid that it won’t work for you here? Well, you don’t have to worry about it, as you’ll have the chance to develop a RDS decoder today! RDS is the short acronym for “Radio Data System” or RDS is a communication protocol standard from the European Broadcasting Union for sending small amounts of digital information using conventional FM radio broadcasts. The use of more and more frequencies for radio programmes in the VHF/FM range made it increasingly difficult to tune a conventional radio to a desired programme. This kind of difficulty is being solved with the Radio Data System (RDS) that has been on the market since 1987. Whether you believe it or not, the RDS has by now conquered all receiver price classes and is nowadays a must in the standard functionality of any radio receiver! Basically, today’s project is a very simple RDS decoder that based on TDA7330B RDS demodulator and AT90S2313 controller. The RDS data is being displayed on a 2×16 character LCD. It will show program… Continue reading

Ultraviolet light box for PCB exposure

Probably everyone electronics hobbyist is dreaming about fast PCB prototyping method. Some of you are just ordering professional made PCBs, that is not always worth of cost, other are using easier way – Laser printer toner transfer technique which is not very accurate, third option is more advanced – ultraviolet light exposure of photo-resist coated PCB through film mask. This gives pretty good quality at reasonable price and doesn’t take much time.   The main thing that is necessary and expensive – the ultraviolet light source that is needed to expose sensitive layer of PCB coating. Yo can buy light source or as a hobbyist you can build one. Scienceprog has published a nice project on how to build a Ultraviolet light source. It uses 8x20W light tubes that gives a total 80W for one side. So the exposure time is just three and half minutes. Device can be used for double sided PCB exposure. And can produce a large number PCBs at once. Probably many of you may not need such big device, but some design ideas may be… Continue reading

RF mail messenger

Is your mailbox standing away from your house? Maybe you would like to know exactly when mail arrives? No problem at all. The guy called newbie123 in AVRfreaks have build a nice system which rings a buzzer when mailbox is opened.   System consist of two parts. Transmitter and receiver. Both parts are controlled by AT90S2313 AVR microcontroller, that can be easily replaced by Attiny2313. Messenger uses the TLP434A transmitter and the RLP434A receiver from SparkFun. The transmitter is mounted inside a small plastic radio shack box. Transmitter is placed at the back of the mailbox so it does not interfere with anything. The antenna is routed down through the bottom and just sticks down under the mailbox. When the mail man opens the door to the mailbox, the ground wire is connected to the circuit and the transmitter powers up, transmitting the 4 byte packet to the receiver mounted inside the house. Cool Toy. Continue reading