This video by Steve of Big Mess o’ Wires demonstrates how to solder a 44-pin chip in a typical TQFP package using the drag soldering technique: The process begins by applying a liberal amount of flux to the pads, then positioning the chip on top. I use a pencil eraser to hold the chip steady while I tack down […]
Category Archives: how-to
Video: Deploying software updates to ArduSat in orbit
Jonathan Oxer VK3FADO gave this presentation at the recent 2014 Linux conference in Perth, Western Australia. The ArduSat project aims to give hobbyists, students and space enthusiasts an opportunity to design and run their own experiments in space. “By choosing a standardized platform based on the hugely popular Arduino hardware design, ArduSat allows anyone to […]
PIC16F1454 used as inexpensive ARM debugger
Peter Lawrence has been working on using a PIC as a CMSIS-DAP ARM debugger. I wanted to see what was feasible in the way of a very-low-cost ARM board. OK, that doesn’t sound original, but stick with me. The solutions that I’ve seen (Tweeny, McHck, mbed, etc.) are limited to wholesale firmware updates. Press a […]
Building a CPLD based logic analyzer
Alex from InsideGadgets has been working on a Building a CPLD Based Logic Analyser. In Part I of his post he details his build of a logic analyzer which saves the sample to external SRAM. For this project Alex used the Altera MAXII EPM240 development board with an on board 20MHz oscillator. The coding was […]
Diode temperature sensor calibration using Arduino and SHT15 module
Paulo writes: A simple diode or the output of a transistor bias circuit can be used as a rough temperature sensor. For this purpose, a calibration procedure using a precise temperature sensor is recommended. This article shows how to calibrate such a temperature sensing circuit using an Arduino and the SHT15 Sensirion temperature/humidity sensor module.
No-connector AVR programming
Steve writes: Here’s a handy trick I developed while searching for ways to reduce the cost and assembly time of Floppy Emu boards. The board has space for a 3 x 2 shrouded IDC header, where the AVR ISP cable should connect. But that connection is only needed once, the first time the AVR is […]
Crystal oscillator frequency pulling
KF5OBS writes: This video briefly explains how to influence a crystal oscillator’s frequency by introducing reactive elements such as trim capacitors and inductors. This example uses a very simplistic Pierce oscillator and a crystal ins series resonance.
RTL-SDR + SDR Radio + Funcube Sat
Amateur radio operator N4JTC has written a blog post about his experiences using the RTL-SDR dongle to receive the Funcube Satellite. With the recent record number of cubesat launches this month most Amateur Radio enthusiasts been busy, myself included. There hasn’t been a better time to get into receiving these satellites. With the inexpensive hardware, […]
Using LTC1100 as precision voltage adapter
Kerry Wong wrote about building a precision voltage adapter using LTC1100: LTC1100 is a zero-drift, precision instrumentation amplifier. Unlike LMP8358, it does not offer programmatic gain setting (the 8-pin package), and the gain is preset at 100. But LTC1100 has several advantages over LMP8358. For instance, while the typical gain non-linearity for LT1100 and LMP8358 are quite […]
ATtiny45 project adds sound activation to PC
Here’s an interesting fun project for the ATtiny45 which lets you wake up your PC by just knocking. Joonas Pihlajamaa posted the detailed project log at CodeAndLife. He describes, “Hardware-wise it’s a simple thing – ATtiny45 emulating a PS/2 device, sending a keypress when three knocks are detected in the attached piezoelectric sensor (or piezo […]
Dynamo powered LED bicycle taillight
Martin uses a dynamo to power his bicycle taillight and wanted to find a way for it to remain lit when the bicycle was not in motion. He sent in this quick hack he used, adding a supercap in the taillight circuit, which powers the light without the need for batteries. Via the contact form.
Receiving, decoding and decrypting GSM with RTL-SDR
Domi007 has been experimenting with using the RTL-SDR dongle to receive and analyze GSM signals for research and academic purposes. He has posted a four parttutorial explaining his use of GNU Radio companion, Wireshark and other open source software to receive and analyze and decode GSM packets. The above link is for part one of […]
App note: Propeller communication with a PC app
Abstract: Many embedded applications share information with external devices, and the preferred connection between devices is asynchronous serial communications. The multicore architecture of the P8X32A enables the designer to create and deploy device-to-device communications strategies with no impact on the primary application code. In this example a deployed communications support cog manages data between the […]
Detecting the Perseids meteor shower using RTL-SDR
Amateur radio operation EB3FRN demonstrates how he used an RTL-SDR dongle tuned to a distant VHF transmitter as a passive radar receiver to view the echoes produced by the meteor’s ionization. The signal he received was from the Graves radar system on 143.050 MHz, using a VHF ground plane connected to the dongle. He displayed […]
Tips and tricks using the 24LC256 I2C EEPROM memories
Jechavarria shared some tips and tricks on using the 24LC256 I2C EEPROM memories: I resume this brief series of articles with another device I usually use. It’s the popular 24LC256 I2C EEPROM memory, from Microchip. First of all, you can find the datasheet here. This memory has a 32K x 8 bytes of capacity (36768 bytes if you […]
Yet another semiconductor V/I curve tracer – II
Kerry D. Wong posted an update on his semiconductor V/I curve tracer we covered previously: In my previous post, I showed my design of a semiconductor V/I curve tracer and discussed its theory of operation in detail. As promised, I will share some of the test results here. If you have not read my previous article, […]
Yet another semiconductor V/I curve tracer – I
Kerry D. Wong writes: Semiconductor curve tracers were frequently used in analog circuit designs many decades ago, at a time when discrete semiconductor devices were in dominance and ICs were scarce. While curve tracers are no longer widely used nowadays due to the ubiquity of digital circuitry and computer aided designs, they are still quite […]
Interfacing the ADS8328 to an MSP430
juani_c has written an article detailing how to interface the ADS8328 to an MSP430: The ADS8328 is a high-speed, low power, successive approximation register (SAR) analog-to-digital converter (ADC) that uses an external reference. The ADS8328 has an internal clock that is used to run the conversion but can also be programmed to run the conversion based on […]
Change HC-05 Bluetooth module settings via AT commands
TechBitar writes, “This is a utility that shows how to change the settings of the ubiquitous HC-05 Bluetooth module using the AT command set. The HC-05 comes with a rich set of AT commands to perform various tasks such as changing the module’s default settings including changing the pass code, the device name, and the […]
Overclocking Arduino UNO with liquid Nitrogen
Michail likes to experiment with overclocking processors using liquid Nitrogen. He also like experimenting with MCU dev boards like the Arduino, which led to the question how far can you go overclocking this little Atmel chip? Why, you might ask. “Because I can. To learn how electronics behave at cryogenic temperatures. And just curios how […]