Soldering iron tip selection guide from Hakko

Arhi contacted us about this useful guide for selecting the right size and shape tip for your soldering iron. First part of the article compares various diameter tips used over the same soldering point. Graphs show that for the fastest work-flow is when using larger or same size tips as the solder point. The second […]

Is soldermask required for fine pitch IC soldering?

Intrigued about a discussion on the forum about whether soldermask is needed between fine pitch pads, Brian decided to test it. In the video of the test he placed solder paste on both the FR4 board material, and the soldermask, as well as some on a tined pad. Once done reflowing his results were in. Both the FR4 and the soldermask acted the […]

Oldest working Weller soldering tool contest

All-Spec Industries anounced the oldest working Weller soldering tool contest. All that is needed to enter is to send a picture of your tool to them, along with your name and shipping adress. First prize is a Weller WD1002T soldering station, and all entries recive a All-Spec Mug Boss. Via the contact form.

What are the topics you need to know to master microcontrollers?

Chuckt asked what goals important to master microcontrollers. There’s been some good suggestions so far, which are consolidated on the wiki: Basic Pins/port/direction (LED flashing) PWM (LED intensity) Advanced UART communication (when and how to use max232 chip) SPI communication I2C communication CAN communication Interrupts (pin – detect button press, UART – communication) Hardware timers Interfacing an […]

SSL/TLS library side by side comparison

Brian stumbled on this side by side comparison of SSL/TLS libraries and gave his review of it: So in summary of what code bases I find usable from a licensing prospective: TropicSSL and axTLS are clear winners in terms of the license CyaSSL and PolarSSL are GPL V2 + FLOSS which is less desirable Next I looked […]

7400 competition entry: Analog comparator

Joseph built an analog comparator for the Open 7400 Logic competition. Using two NAND 3-input gates and a D-type flip-flop, he build a clocked analog comparator. After reviewing the internal composition of a CMOS NAND 3 gate he noticed that two of them connected in the right way make up a comparator. To make his own version he used a D-type flip-flop to […]

How-to use surface mount parts with a breadboard

Pppd shared a tip for using surface mount parts with a breadboard, mount them on 0.1″ pin header: Also, I’m probably not the first one to do it this way… but if you don’t like through-hole parts just as much as I hate them you may want to use surface mount resistors, capacitors or even […]

Voltage monitor for car’s battery and its charging system

Raj designed a car battery volt-meter. The core of the project is a PIC16F1827 which uses its internal fixed voltage reference FVR and ADC to precisely measure the battery voltage. Measured voltage is displayed on a 4 digit 7 segment display. His circuit is connected to the car’s battery through a standard car lighter jack. Via the […]

I2C controled 8 relay driver switches plug-in devices

Megabug posted his I2C relay driver board for controlling 8 outputs. It controls 8 relay switches in which one pin of each switch is common, while the other pins are available through 8 screw type headers. It uses the PCA9554 8bit I2C port expander to drive a ULN2803A buffer which in return drives the relay coils. All buffer input […]

#FreePCB via Twitter to 2 random RTs

Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]

7400 competition entry: Animated LED Christmas sign

Raj entered his Animated LED Christmas sign into the Open 7400 Logic Competition. Having already build a PIC controlled version, he wanted to try and control the sign using discrete logic only. The individual letters are build from red LEDs and run of a 32V power supply. Check out the video of this project below. Via […]

HAKKO soldering pencil driver update

Arhi compares his soldering iron driver with commercially available products. After designing and building a open source soldering station for Solomon or Hakko soldering pencils, he posted a full analysis of his project. While his driver has some overshoot, once it stabilises the temperature has less swing then the original drivers. With some PID tuning even better […]

Controllable aquarium moonlight strip

Theatrus build a controllable aquarium moonlight strip. Royal-blue Osram high power surface mount LEDs provide the lighting, and an ATmega88 the control. RS485 port is used for control. All of the design files should be available shortly. Its quite potent (visible with the main 6x80W T5s running). Its easy to mount (a handful of command strips […]

IR helicopter automatic altitude control

Amieres built a IR controlled Helicopter with Wiimote using USB IR Toy V1. A camera connected to the laptop tracks the helicopter. Using the USB IR Toy the laptop sends automatic altitude control signals. Setting attitude points is done with Wiimote’s up/down buttons, while nunchuk joystick is used for motion control. Via the comments. You can get […]

7400 competition entry: Masochist’s video card

Chris entered his Masochist’s video card into the Open 7400 Logic Competition. Using only discrete logic his circuit cycles through 8 presettable colors at a variable frequency. Using a simple resistor network he outputs it over the VGA output. It is well documented and all the design files are available. Check out the video below. Via […]