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Circuit Cellar's editorial team comprises professional engineers, technical editors, and digital media specialists. You can reach the Editorial Department at editorial@circuitcellar.com, @circuitcellar, and facebook.com/circuitcellar

New GaAs MESFET Chips

BeRex recently began shipping the BCF-series family of GaAs metal–semiconductor field effect transistor (MESFET) chips. According a press release, the family “addresses the need for low phase noise with high gain and power in applications such as single and multistage amplifiers, oscillators, synthesizers, etc. ranging in frequency from DC to 26.5 GHz.”

You can use the MESFET chips for both broadband and narrow-band applications from DC to 26.5 GHz. A typical application requires a high level of Output Third-Order Intercept Point (OIP3) linearity and a low phase noise that cannot be easily achieved with other technologies, BeRex announced.

Seven devices comprise tje BCF-series family. Each device is built utilizing a 0.25-µm gate length and with a gate width of 200, 300, 400, 600, 800, 1,200, or 2,400 µm, depending on gain and power requirements (up to 1 W for the largest 2,400-µm device).

[via BeRex]

Elektor I/O Shortage & Complexity

One of the many projects featured in the double-sized July/August edition of Elektor magazine is an I/O Warrior Expansion Board. The article outlines how to create a multifunctional board sporting a vast number of inputs and outputs, making it ideal for a variety of industrial control applications via a PC.

The small universal interface card uses the IO-Warrior56 Module from Code Mercenaries. You can add it to an old PC, notebook, or laptop in order to convert it into a measurement-and-control hub, making good use of any redundant hardware you have in storage. The versatile chip enables you to automate a building (e.g., your home, greenhouse, microbrewery, etc.) or any quasi-industrial process you’ve always wanted to put into operation.

Available in the Elektor Store, the preassembled IO-Warrior56 Module provides an easy-to-use, full-speed USB interface and a built-in temperature sensor. It is uncomplicated to talk to using a Visual Basic or C/C++ program. No complex programming! Source code is available that works with the free version of Visual Studio.

The Elektor-designed IO-Warrior Expansion Board is spaciously laid out with through-hole components for easy reproduction at home or in the lab.

Detailed instructions on how to program the IO-Warrior board’s peripherals in Visual Basic are found in the Elektor magazine article that’s dedicated to the IO Warrior project.

CircuitCellar.com is an Elektor International Media website.

Teaching Photonics with Lego Bricks

To inspire children to get involved in science you need low-cost, open-source, learning-by-doing projects with a high cool factor. A Lego-based Michelson Interferometer developed by the University of Osnabrück is all that. Professor Mirco Imlau presented their project at the open hardware fest EHSM.

Source: EHSM

Source: EHSM

The second edition of the Exceptionally Hard and Software Meeting (EHSM) took place in Hamburg June 27-29. True to its tagline “pushing the frontiers of open source & DIY,” the meeting drew a crowd of people doing remarkable things in the field of open science and open soft and hardware. Subjects ranged from learning how to make synthetic diamonds which are used in experiments for quantum computing, the presentation of the first mostly open source hardware camera and an introduction to a DIY device to produce printed circuit boards.

One of the speakers was Mirco Imlau who heads the Ultrafast Physics Research Group at University of Osnabrück. Imlau explained he is looking for ways to playfully teach kids about photonics so that by the time they’ll join his classes they already have internalized knowledge about the field.

Imlau and his collegues did some serious research about what a project needs to appeal to kids and came up with a set of basic rules. Children aren’t the most affluent of citizens so the project needs to be low-cost. The required components for photonic experimenting also need to be easily available. That’s why the team turned to Lego. A third important factor is appeal and lastly the project needs to based on the principles of open hardware. That means a rich environment of instruction manuals and video’s, platforms to exchange ideas and the possibility to look under the hood. All that is available at the MyPhotonics website.

Combining all these principles the team developed a project for kids to build a historic optical experimentation device: the Michelson Interferometer. A tool to measure the qualities of optical beams. Imlau pointed out that another important aspect between failure and success is that the project once constructed should function properly. So for instance, the Lego mirror mount has the same functionalities as its professional counterpart, like 2-axis adjustment and reflection suppression. The result is a fully functional Lego-based Michelson Interferometer with a price tag of approximately $194 (€142) against approximately $3900 (€2,870) should professional components be used.—Tessel Renzenbrink, TechTheFuture.com

[via TechTheFuture.com]

TechTheFuture.com is Elektor International Media publication.

WIZnet Design Challenge Deadline August 3 (Sponsored Post)

The WIZnet Connect the Magic Challenge deadline is fast approaching — ​August​ 3, 2014! This is your shot to win a share of $15,000 in prizes and gain international recognition as innovator!  We encourage you to finish up your Entry and submit!


Essential info follows:

  • ENTRY TIPS: Participating is simple. Go to the TIPS page
  • ENTER: To Enter, simply upload your Entry via ENTRY DROPBOX
  • PRICES: Check out the great PRIZES

If you already submitted an Entry but want to update something, you must do so before the deadline.


Didn’t finish your project? Consider this!

If the deadline approaches and your entry is not complete, we still encourage you to submit your project. While only these on-time files are submitted to the judges, consider that there are many more opportunities for contest success, such as Elektor/Circuit Cellar’s “Distinctive Excellence” awards.

While Elektor/Circuit Cellar must follow the Sponsor’s rules about submission and judging when it comes to the contest’s official prizes, Elektor/Circuit Cellar is able to include its own award program that takes into account design skills that may otherwise go unrecognized. By submitting even an unfinished project by the deadline for official judging, you qualify for a Distinctive Excellence review. If there is merit and the project warrants further consideration, those projects that may be offered a Distinctive Excellence award may be updated by the entrant after the contest deadline.

Historically, there have been some really fascinating Distinctive Excellence projects for previous Elektor/Circuit Cellar design contests. Those who win this designation see their projects posted online similar to the official winners and enjoy much of the same exposure. Many are offered separate print magazine publishing deals through Elektor/Circuit Cellar. The benefits of having Elektor/Circuit Cellar recognize and publicize your work in a high profile campaign like this should not be underestimated.

Plus …

Due to Elektor/Circuit Cellar’s international reach, you’ll get even more exposure than ever before! Imagine getting a Distinctive Excellence award—or getting your article published—and being recognized by readers throughout the world! That could lead any number of positive outcomes … Job opportunities? Design deals? The sky is the limit!

Challenge Administrator: Elektor International Media

Sponsor: WIZnet

New Raspberry Pi Model B+

The Raspberry Pi foundation announced what it calls “an evolution” of the Raspberry Pi SBC. Compared to the previous model, the new Raspberry Pi Model B+ has more GPIO, and more USB ports. In addition, it uses Micro SD memory cards and improved power consumption.

Source: Raspberry Pi Foundation

Source: Raspberry Pi Foundation


The GPIO header is now 40 pins, with the same pinout for the first 26 pins as the Model B. The B+ also has four USB 2.0 ports (compared to two on the Model B) and better hotplug and overcurrent behavior. In place of the old friction-fit SD card socket is a better push-push micro SD version.

In line with today’s electronic concepts, the new board also lowers power consumption. By replacing linear regulators with switching ones, the power requirements are reduced by between 0.5 W and 1 W. The audio circuit incorporates a dedicated low-noise power supply, enabling better audio applications.

The new board is well organized. The USB connectors are aligned with the board edge, and the composite video now has a 3.5-mm jack. The corners are rounded with four squarely placed mounting holes.

The Raspberry Pi Model B+ uses the same BCM2835 application processor as the Model B. It runs the same software and still has 512-MB RAM.

If you want to adapt a current project to the new platform, be sure to study the new GPIO pins and mechanical specs. To ensure continuity of supply for industrial customers, the Model B will be kept in production for as long as there’s demand for it.

At $35, the new model B+ is the same price as the older model B and is already available from Farnell/element14/Newark and RS/Allied Components.

[Source: www.raspberrypi.org]