USB MultiComms part one – USB Board

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Brian Dorey has been working on a USB communications box project:

Several of the projects we have been working on recently needed some form of serial communication with our PC, either through RS232, UART, I2C or SPI and at the moment we use a handful of different USB to serial adapters designed for each different protocol.  One problem we have run into before is ground loops between the PC and the devices under test can occasionally cause problems.  What we needed was a single communications box that works with all of the normal communications protocols and is isolated from the PC.  After looking at some of the isolated USB to RS232 converters that are on the market we decided that we would build our own.

Project info at Brian Dorey’s blog.

DIY capacitance meter

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Electro-Labs created new open source hardware project,  a DIY capacitance meter:

This is a capacitance meter which can measure capacitors rated from picofarads to millifarads. The principle of operation is simple. Just apply voltage to the capacitor and measure the elapsed time to charge it. The circuit is based on Atmega328P and it is Arduino IDE compatible. It includes the voltage regulators which output 5V and 3.3V from 9V input. A Nokia 5110 LCD is used to display the measured information. Thanks to the 4mm banana jacks, various kinds of probes can be used such as SMD probe, crocodile probe etc.

More details at Electro-Labs project page.

Via the contact form.

 

 

Bus Pirate SPI sniffer using RealTerm for highspeed transfer

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pyblendnet-js  writes:

The Bus Pirate has at least three other out-of-the-box methods of sniffing SPI data from a Master and Slave communication:
– The Bus Pirate GUI
– Bus Pirate SPI Sniffer Utility
– Third party tools such as the Sump Logic Analyzer Client – an example here.

I believe the fastest of these may be the sniffer utility. I used BusPirate.SPIsniffer.v0.3 application with a version 3.0 Spark Fun Bus Pirate Clone to sniff the SPI data between a microcontroller and a BK2421 tranceiver slave device from an MJX RC helicopter. This was fine to grab the initialisation sequence but the 115200 baud FTDI USB link to the laptop could not keep up long after that. I was able to interpret the hex code grabbed using my own parser – see my GitHub project at ParseSPI.
For higher speed comms, I discovered the solution had been found on this post:Using Bus Pirate with SPI Sniffer. Armed with this, the Bus Pirate SPI API and the Real Term help file, iwas able to develop this small console program in visual basic (VS2010) to automate the process of receiving the sniffed data at 800000 baud.

Via the forum.

App note: Heat sink mounting guide

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Fairchild Semiconductor’s app note on proper heat sink mounting to achieve lower thermal resistance between the package and its heat sink. Link here (PDF)

This document provides guidelines for mounting heat sinks for the proper thermal management of power semiconductor devices in field applications. This document describes heat sink mounting methods, considerations, contact thermal resistance, and mounting torque for various packages.

Free PCB Sunday: Pick your PCB

IRToy

We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

Continue reading “Free PCB Sunday: Pick your PCB”

App note: Understanding thermal dissipation and design of a heat sink

Application report from Texas Instruments on heatsink designs. Link here (PDF)

Power dissipation performance must be well understood prior to integrating devices on a printed-circuit board (PCB) to ensure that any given device is operated within its defined temperature limits. When a device is running, it consumes electrical energy that is transformed into heat. Most of the heat is typically generated by switching devices like MOSFETs, ICs, etc. This application report discusses the thermal dissipation terminology and how to design a proper heatsink for a given dissipation limit.

Free PCB coupon via Facebook to 2 random commenters

BP

Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times every week:

Continue reading “Free PCB coupon via Facebook to 2 random commenters”

A hack for Hacks using AnalysIR & USB IR Toy

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The crew from AnalysIR  writes:

One of our users from Italy, Guido, was tasked with upgrading an old in-house WRC system to allow the team of Sport’s Journalists to access the rack of satellite receivers relaying the various sports events around the building.  The challenge is that all of the STB (Set Top Boxes) are located in a dedicated room away from the Journalist’s desks and it is impractical for them to manually change the stations when working to tight deadlines. Previously there was a system in place to remotely switch feeds, but Guido needed to upgrade the system to handle the ever growing number of devices and Infrared protocols. Luckily, he found AnalysIR during his research to implement ‘a hack for Hacks using AnalysIR‘.

Via  AnalysIR.

Check out Guido’s full project description here.

#FreePCB via Twitter to 2 random RTs

KHOS-2-3-4-5-6P 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 it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter with a coupon code for the PCB drawer.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

App note: Fast charging control with NTC temperature sensing

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Vishay’s application note on fast charging control using NTC and TI’s BQ2005. Link here (PDF)

The need for increased autonomy for new models of laptops and cellular phones has resulted in high-energy density power packs – Ni MH and Li-ion batteries. These batteries can be charged quickly, on the condition that the fast charging complies with several criteria.

The sophistication of the electronic system depends principally upon cost and upon the requirements of the batteries. Often, the fast charging is monitored by an IC, measuring  the voltage of the batteries, the char-ging current via a sense resistor, and measuring the temperature of the batteries via one or several Negative Temperature Coefficient (NTC) thermistor(s). The IC’s are almost always in the chargers or integrated in the battery pack (Li-ion). The thermistors are almost always integrated in the battery packs, sometimes placed in the charger, and/or in the final apertures (low cost cellular phones).

This application note  explains how to design an NTC thermistor from Vishay BCcomponents for a BQ2005 from TEXAS INSTRUMENTS dual Ni MH batteries charging IC.

Free PCB Sunday: Pick your PCB

KHOS-2-3-4-5-6P-600x400

We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

Continue reading “Free PCB Sunday: Pick your PCB”

App note: VSOP98260 for IR code learning applications

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Application note from Vishay on their VSOP98260 IR learning chip which uses the same IR LED as transceiver. Link here (PDF)

There is a wide interest in universal remote controls, which can be used to diminish the “clutter” of remote controls typically present in a modern living room setting. Training the universal remote to send the correct code to each of possibly many appliances in any media setting is not a simple task.

Infrared remote controls transmit their signals via an infrared LED. The simplest and least expensive code learning technique devised to date uses this same infrared LED as both the code transmitter and the code detector for receiving signals from the appliance remote. IR LEDs are not very efficient detectors. Fortunately, for code learning we want to use an inefficient detector to eliminate any spurious signals present in the room. The much stronger signal from the appliance remote, which is held close to the detector, will be enough to capture a clean signal.

Free PCB coupon via Facebook to 2 random commenters

BP

Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times every week:

Continue reading “Free PCB coupon via Facebook to 2 random commenters”

DIY WiFi gas detector with text alerts

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Stefan over at Hackster.io has written an article detailing his DIY Wi-Fi gas detector that sends SMS alerts:

Hey guys, back with another little project that I’ve been fiddling with for the past week. With kids around, every parent is thinking how to make their home safer for the little ones and for everybody in general. One of the most dangerous thing in the house can be the stove and since we have a gas-powered one, I always wondered why there are no simple gas detectors that can be used around the stove, just to alert instantly that gas may be leaking.
Well, that was the moment when I decided to build one of my own. Having a Particle (Spark) Photon lying around, I decided to use that as a foundation for the project. I like the fact that they are very small and cheap, and also can be flashed over the Wi-Fi. Having that settled, I needed the gas sensor and some kind of alerting system.

Project details at Hackster.io.

XinSound Fuzz FD-20 mod – Big Muff V2 Ram’s head clone

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Davide Gironi writes,  “The XinSound Fuzz FD-20 is a Big Muff V2 Ram’s Head guitar pedal clone.  It’s schematic is next to the Electro Harmonix Big-Muff Pi 1975-15-10 original circuit. As usually, I would like to experiment on this pedal, doing some mods.”

Project info at Davide Gironi’ blog.

Check out the video after the break.

Continue reading “XinSound Fuzz FD-20 mod – Big Muff V2 Ram’s head clone”

Home automation with Telegram BOT

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Luca Dentella has written an article describing how he developed a bot to control his Raspberry Pi via Telegram:

 The project I’m going to describe today it’s a sort of proof of concept that will demonstrate the possibility to remote control sensors and actuators (for example a couple of relays) via Telegram.
Telegram is an instant messaging application, similar to the famous Whatsapp. Last June, the Telegram developers announced that a new set of APIs were available to develop bots.
My idea was to develop a bot, running on my Raspberry Pi, that receives commands via Telegram chats.

Project info at Luca Dentella’s blog.

Check out the video after the break. Continue reading “Home automation with Telegram BOT”

2015 Release Candidate Branch And RC1

Kicad

Kicad announce 2015 Release Candidate 4.0.0 RC1:

We are pleased to announce that KiCad has finally made a 2015 release branch. The 2015 stable release of KiCad will start from version 4.0.0. Currently we are in the release candidate phase and as such BZR 6188 is now known as 4.0.0 RC1.
The 4.0 branch can be found here: KiCad 4.0 Branch
The RC1 branch has been packaged as a archive available here: KiCad 4.0.0 RC1 Archive
The new GUI translations can be found in the kicad-i18n repository on github.

More details at KiCad site.

Thanks for the tip spanner888!

#FreePCB via Twitter to 2 random RTs

IRToy-600x369

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 it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter with a coupon code for the PCB drawer.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

App note: Fundamentals of electronic security: Tampering with the easy targets

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An app note from Maxim Integrated about tampering electronic securities through physical means and how to protect against it. Link here (PDF)

More and more frequently, computer-based systems store valuable data and manage the flow of valuable commodities. If an opponent can gain control of the computer that touches this valuable data, they can access your private information, steal your money, or fraudulently access goods and services. In this article we look at tampering and what we can do about it.