by EEVblog @ youtube.com:
Dave shows you how to reverse engineer a PCB to get the schematic. In this case the new Rigol DS1054Z oscilloscope.
How does the discrete transistor analog front end and the software bandwidth limiting work?
How do you decode SMD transistor codes?
How does it compare to the old Rigol DS1052E?
Dave also discusses the low voltage ohms function of a mulitmeter, how it’s useful, and how to test your multimeter to see if it will have any issues with in-circuit testing.
EEVblog #675 – How To Reverse Engineer A Rigol DS1054Z - [Link]
Geir Andersen over at LetsMakeRobots has designed and built this cool solder paste dispenser:
As I’m doing SMD prototypes I wanted to do reflow soldering instead of hand soldering and needed a solder paste dispenser.
The professional ones are not that expensive but you need an air compressor and I was trying to avoid that extra cost and noise. So I came up with this design.
It uses a PICAXE M14 microcontroller and ULN2003 Darlington driver to run the 28BYJ-48 stepper motor. As a stepper the 28BYJ-48 sucks with its gear ratio, but for this purpose it is cheap and has lot of torque. For my type of work and one-off prototypes it works great.
DIY solder paste dispenser - [Link]
This project is a USB to Serial converter using an ATMEL AVR microcontroller. There are two version of the converter, one with SMD parts and another with TH parts. The mcu used is an ATmega8 and USB communication is done using software on AVR mcu. It’s based on the software USB implementation of AVR-CDC. Firmware can be downloaded from the download section of CDC-RS232.
USB to Serial Converter using AVR microcontroller - [Link]
Just a short video to show how I hand solder a ceramic leadless chip carrier (CLCC) package to a circuit board, in this case, a Si570. Typical surface mount soldering techniques, including the use of flux, fine gauge solder, and a fine tipped iron.
How to solder a leadless ceramic surface mount package - [Link]
This page provides documents about a cheap SMD solder station built as an Arduino shield (Arduino UNO). It supports active soldering tips from Weller (RT series) which contain the heating element as well as a sensor and provides a standard 3.5 mm jack. Together with the corresponding female connector you will get a compact SMD soldering iron (see pictures below) with very fast heat up times of a few seconds.
SMD Soldering Station for Weller Soldering Tips - [Link]
by Dave Young
Anyone who has learned a layout package like EAGLE and sent a board off to a fab knows the trepidation felt when submitting the final gerbers. It doesn’t matter if the order is for 3 PCBs or 3,000 PCBs. The time lost from an error can ruin a project’s momentum, especially if it is a boneheaded error.
There is a better way to check all of the footprints with a layout: Paper PCB Protos. This low-tech technique only takes an hour, but can provide 100% confidence in the footprints checked. Thanks to proper scaling of the PCB, it is possible to create a PDF and print out an exact representation of the board. The designer can then place parts on the paper to quickly determine if a component’s footprint will be suitable, at least for a pilot production build.
Using Paper Protos to Check Footprints with EAGLE - [Link]
Instructions for Soldering and Desoldering SMDs featuring up-close shots of fine-pitch soldering.
Surface Mount Soldering 101 - [Link]
An Arduino-compatible smart outlet designed to instantly turn your toaster oven into a reflow soldering station.
Advances in technology continue to shrink the size of components. Hobbyists, who have traditionally worked with through-hole parts, are finding these parts harder and harder to come by as more parts become unavailable in through-hole variants.
Soldering surface mount components with a soldering iron, while possible, can be a rather tedious task. In particular, when you’re working with densely packed pins like those of a microcontroller, hand soldering a board quickly becomes a daunting task.
Reflowster – Soldering Controller for Surface Mount PCBs - [Link]