Electronics-Lab.com Blog

New version of Attend connectors for SIM cards replaces the current one. To make it to you easier, we will keep in stock both types for some time.

It is the six-pin „push-push“ type 115A-ADA0-R02, which will replace the older almost identical type 115A-ADA0-R01. New type differs from the older one only in the width and a position of side mounting lugs, which are soldered on a PCB. Lugs of the new type are somewhat closer to the middle of the connector and they are narrower. The difference is probably best illustrated at the enclosed pictures. Both types also contain a switch for SIM card detection. Detailed information will provide you the 115A-ADA0-R02 and 115A-ADA0-R01 datasheets.

Migrate to a new type of a SIM card connector Attend - [Link]

dangerousprototypes.com writes:

Ben Eishen sent in this link. He says, “I have been thinking about building an ESR meter, and this one looks like a winner.” The design is based on the ATMega88 and according to the designer, Dr. Le Hung, “The LCFesR 4.0 unit is a precise, wide range meter that can measure inductivity, capacity, frequency and equivalent series resistance of a capacitor in-circuit, which can be easily built with homemade one- or double-faced PCB and available electronic components.” The video above shows the LCFesR measuring component values as compared to values determined by a commercial unit.

The schematic and documentation can be found on Dr. Le Hung’s website.

ATMega88 based LCFesR meter - [Link]

The Air Quality Egg is a sensor system designed to allow anyone to collect very high resolution readings of NO2 and CO concentrations outside of their home. These two gases are the most indicative elements related to urban air pollution that are sense-able by inexpensive, DIY sensors.

Air Quality Egg - [Link]

Four Walled Cubicle – AVR Articles. Dean writes – [via]

Over the years I’ve written a few fairly lengthy tutorials relating to AVRs. Originally, I posted these over on the AVRFreak’s Tutorials forums, but after many requests for PDF versions and after becomming frustrated at the lack of typesetting expressiveness given in the forum software, I converted over the text into LaTeX.

Now the tutorials are available in PDF form, and can be freely redistributed under an MIT license. I’ve even put up a public mirror of the tutorial LaTeX source SVN repository, so that others can fork off and examine past revisions of the files as I update them in the future.

AVR Articles - [Link]

swim timer for night swimmers @ DougsDIY – [via]

swim with a triathlete group in an outdoor pool at 6AM three days a week. For half the year I can see stars when I start swimming. What I can’t see in the dark is the analog clock to check my pace on 100 meter laps.

To solve this problem I designed and built a portable digital timer with LED display. The 4-digit 7-segment display is large enough to see from 10 feet away so I can read it without stopping. The timer is encased in a transparent and waterproof polycarbonate tube so that I don’t have to worry about it getting wet or falling in the pool. In fact you can take it to the bottom of the pool and it won’t leak. Normally it just sits on the edge of the pool where I can see it.

There are a variety of LCD swim timers available that are fine for day swimmers. This timer is for night swimmers.

Arduino based swim timer for night swimmers - [Link]

www.adafruit.com writes:

Yesterday, I published a post about opamps here on the blog. This post utilized a new feature here at Adafruit: rendered LaTeX equations. For those that are unfamiliar, LaTeX is a markup language for the TeX system, originally developed by legendary computer scientist Donald Knuth. LaTeX (pronounced “Lay-Tek”), is used by scientists, educators and engineers around the world to format equations so that they look nice and neat, and are easy to read.

About a month ago, in the course of originally drafting that opamp article, I started looking around at LaTeX plugins for WordPress. There are several of these available. All of them have their strengths and weaknesses, but eventually I settled on WP-QuickLaTeX by Pavel Holoborodko, Dmitriy Gubanov and Kim Kirkpatrick.

WPQL supports automatic equation numbering, has built in tikz and pgfplots support, can render alpha-channel PNGs, and supports LaTeX markup in blog comments, which means that the conversation can go both ways. TeX and LaTeX have been around a long time, so there is information all over the place about how to use it, but here are a few tutorials (1, 2)

LaTeX Rendering for WP - [Link]

Richard Comerford writes:

More than ever, cameras are becoming a part of the personal and business devices we carry in our pockets. While the light levels at which today’s photographic image sensors can work is extremely low, having flash lighting means users can capture greater detail at faster speeds. And to be sure that flash systems do not consume a lot of the power budget of these battery-run portable electronics, designers have turned to using LEDs as the light source, rather than the traditional xenon tube.

A broad array of devices is available today for driving LEDs as flash devices. Many can deliver high current so that LEDs can be driven to maximum output. However, the increased efficacy of today’s LEDs – meaning they can deliver more light from less current – means that drivers can also focus on reducing current drain on batteries.

Five Solutions for Driving LED Flash in Mobile Devices - [Link]

Steve Taranovich writes:

Home energy systems based on renewable sources, such as solar and wind power, are becoming more popular among consumers and will gain increasing support from governmental bodies.

In this article, the power inverter will be discussed in the context of solar energy, especially as it relates to the latest, low power microinverter architectures that make the most sense in converting a photovoltaic (PV) panel’s DC output to an AC signal for residential use.

Microinverters are installed on each individual PV panel and typically handle 300 W. Microinverters provide the benefit of scalability for those who want to start small, yet have full DC/AC conversion with maximum power point tracking (MPPT). Many people want to put their excess power back onto the power grid, which will speed up the return on investment (ROI) time and ultimately could lead to freedom from grid reliance. The technology that will enable ubiquitous architectures like this on our roof is getting closer.

An Engineer’s Guide to Power Inverters for Solar Energy Harvesting - [Link]

open-electronics.org writes:

A modem GSM & GPRS with SIM900 or SIM908 module. Allows you to create data connections on the GSM network through a standard USB interface. The cellular modems, particularly USB-stick ones, are now at very affordable prices, however they’re limited: they are explicitly designed for Internet connections, so you cannot use it as a normal modem and so implement, for example, a point to point data communications with them. The GSM modems that allow this are quite rare, and so we create and offer you one: it is a device for PC with an USB interface with “voice” functions: there is a jack for a speaker and one for microphone.

GSM/GPRS & GPS modem with SIM900/SIM908 module - [Link]

photo via watterott.com

Ibrahim KAMAL writes:

Today I am going to talk about low cost and effective image processing for very specific embedded applications. I am not talking about robots recognizing their environment or finding their way to a power plug, but rather using small CMOS camera as better sensor. We have used this technology for various clients in our consulting service, so I am not going to get into the very specifics of any of those applications cause it would be a breach to our NDAs. Still,  IKALOGIC aims to educate and share knowledge to the world. Considering that, I thought about writing a short tutorial, showing to beginners how to get started in that rather intimidating field.

CMOS camera as a sensor - [Link]