Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

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

Tiny pocket password reminder

Probably everyone has a long list of passwords to remember. But are they safe from other and from forgetting them. Some people are using same password for all cases…well this is not safe. And of course using popular words as passwords also isn’t safe. It is better to use characters mixed with numbers. But these are hard to remember.   Alberto ricci bitti have built a fancy embedded pocket password reminder which can remember hundreds of passwords. The circuit is simple – menu navigation is done with encoder rotor and single button. Information from Cypress CY8C27443 microcontroller is displayed on 2×16 character LCD display. In order to access passwords you need to enter 5 digit code by rotating and selecting symbols with rotor encoder. But the most interesting thing in this project is how password information is captured from PC. Device have a phototransistor which is used to read data from PC monitor. Author have developed simple web script which allows to enter password with on screen keyboard. Then phototransistor pointed to special screen area reads the code which is… Continue reading

Multiple PIC16F84 Proteus simulated projects

Proteus is a software tool that allows simulation of various circuits including microcontroller based ones. You can complete entire project with simulator including hardware and software parts. And only then you can move towards manufacturing real device. This page is dedicated only to PIC16F84 microcontroller projects where you can download ready to simulate about 31 complete project.   Projects include implementation of popular interfaces like LCD, Timers, EEPROM writing, Interrupts, I2C and 1-wire communication, motor control and so on. Each project include Proteus project file and microcontroller hex file that has to be attached to model to start simulate. Page is in Spanish language, but it is easy to navigate, or just use any online translator. Continue reading

Universal RC5/RC6 transceiver with LCD indication

Universal RC5/RC6 transceiver is originally developed by Frits K. Raalte. It is a nice tool to analyze RC5, RC5X or RC6 IR signals. Also it can transmit every possible RC5, RC5X or RC6 protocol based code like a IR remote control does.   Device is capable to receive signal and display its code on LCD as decimal and binary code(meanings of codes see here and here ). Additional three LEDs indicate receiving phase(green), toggling between decimal and binary code on LCD is indicated by yellow LED and red LED indicates bad code or unknown standard. When transmitting IR code, there is one button which allows to adjust code and another is for sending command. This way any code can be sent. I wouldn’t call this toy a universal remote as it would be un convenient to select codes each time when you want to lets say change channel or change volume. It is more for testing purposes, where it is a “must have it”. Project files are available for download (Circuit, PCB and binary for PIC16F268 ). Continue reading