Electronics-Lab.com Blog

Asgard build this Rapper project:

What this is, is a small device that records a command sequence for a TV remote control, then emits the same sequence when activated by a pulse detected in a piezo transducer. Such pulse can be as simple as rapping your knuckles on the table where the Rapper is placed. Typically the Rapper would record the mute control for the TV, so that you can run to get the phone without having to hunt down the remote control for the TV. Cute, eh?

[via]

Rapper project - [Link]

Teardown: Samsung Galaxy S4 - [Link]

Have you ever wanted to send data from a sensor or project wirelessly? This simple circuit allows you to build your own wireless transceiver using two ICs, a transistor, and two resistors. The IC is from Melexis and uses On-Off Keying modulation and can be battery powered.

Here is the circuit.

DIY Wireless Data Transceiver - [Link]

Recently many little boards running Linux appeared across the globe. These boards may prove useful for many projects and for teaching Linux OS to any enthusiast out there. But how we got there? Read about the road to development of these embedded computers. (by Publitek European Editors)

Linux has long been on the edge of breaking into embedded systems, but one barrier has been the lack of affordable development boards with fast enough processors and large enough storage to cope with Linux. In the last few years, the situation has changed and there are a number of low-cost development boards, each with an array of plug-in peripherals and carrying processors with the power and memory to comfortably execute Linux-based applications. This article will look at BeagleBoard/BeagleBone and PandaBoard. It will also look at a manufacturer’s approach to the same problem – The Freescale Tower development system with a special emphasis on the MPC8309 PowerQUICC II Pro processor.

Linux and the Road to Development - [Link]

element14 is proud to offer an advanced “first look” at the next-generation BeagleBone –  one of the most popular open source hardware platforms developed. The new BeagleBone boasts even more memory and higher performance than previous generations.

Availability is slated for the April timeframe, but students and hobbyists can register thier interest in receiving a BeagleBone now on the element14 engineering community. Plus, leading up to the official launch, open hardware enthusiasts and BeagleBone fans are invited to join element14’s Open Source Group to share ideas, exchange code, read reviews of the device, and sign up for the free Engineering 101 webinar series produced by the top experts in the electronics industry.

element14 offers sneak preview of next-gen BeagleBone - [Link]

Common methods of reverse-voltage protection employ diodes to prevent damage to a circuit. In this article alternative methods of using relays are discussed. This way achieve zero voltage drop on the circuit and effectively protect the system.

Simple reverse-polarity-protection circuit has no voltage drop - [Link]

Meet Powah designed and build a little power on/off toggle with an indicator LED. He writes: [via]

It is designed to mount on one end of my breadboard, so as to reduce the wear and tear caused by excessive insertions of power bus leads. The board is approx 1 cm^2.

Power toggle switch with an indicator LED - [Link]

A smaller version of the Raspberry Pi computer built in the UK is driving the cost to under $25. [via]

element14 has announced the launch of the new credit card sized Raspberry Pi Model A board in Europe, selling at under $25. It uses the same 700MHz ARM1176 Broadcom BCM2835 processor but only 256MB of RAM is included as standard, there is no Ethernet connection and only one USB port, but it does use considerably less energy for battery-powered applications.

Smaller Raspberry Pi costs under $25 - [Link]

APC 8750 is a mini PC runs a custom Android system, built for keyboard and mouse input. A basic selection of applications is preinstalled. Also included is a full set of consumer I/O ports, enabling APC to connect to your PC monitor or TV.

Powered by a VIA WonderMedia ARM processor, Android PC system (APC) integrates memory, storage, and a full set of consumer I/O features in a small footprint Neo-ITX motherboard. The system also features a custom build of Android that has been optimized for keyboard and mouse input, and comes with a browser and a selection of preinstalled apps.

• Optimized Android OS
• HD TV support
• Hardware acceleration of the most demanding video formats
• VIA WonderMedia ARM 11 SoC
• 2 GB NAND Flash Memory
• 512 MB DDR3 SDRAM Memory
• VGA and HMDI display ports
• Four USB 2.0 ports
• One microSD slot
• One 10/100 Ethernet port
• Audio-out/ Mic-in
• 9 VDC power socket (2.5 mm, centre pin positive)
• Neo-ITX form factor (170 x 85 mm)

Internet PC for €52 - [Link]

Building my Own Laptop @ bunnie’s blog – [via]

We are building an open laptop, with some wacky features in it for hackers like me.

This is a lengthy project. Fortunately, ARM CPUs are getting fast enough, and Moore’s Law is slowing down, so that even if it took a year or so to complete, I won’t be left with a woefully useless design. Today’s state of the art ARM CPUs — quad-core with GHz+ performance levels — is good enough for most day-to-day code development, email checking, browsing etc.

We started the design in June, and last week I got my first prototype motherboards, hot off the SMT line. It’s booting linux, and I’m currently grinding through the validation of all the sub-components. I thought I’d share the design progress with my readers.

Of course, a feature of a build-it-yourself laptop is that all the design documentation is open, so others of sufficient skill and resources can also build it. The hardware and its sub-components are picked so as to make this the most practically open hardware laptop I could create using state of the art technology. You can download, without NDA, the datasheets for all the components, and key peripheral options are available so it’s possible to build a complete firmware from source with no opaque blobs.

Bunnie is building an open-source hardware Linux laptop - [Link]