Buck-boost regulator achieves high efficiency


by Susan Nordyk @ edn.com:

Using adaptive current-limit PFM (pulse frequency modulation) control, the ISL9120 switching regulator from Intersil realizes efficiencies of up to 98%, while automatically transitioning between buck and boost modes without significant output disturbance. The part accommodates a wide input voltage range of 1.8 V to 5.5 V and has an adjustable output voltage range of 1 V to 5.2 V for use with multiple power rails. It is capable of delivering up to 800 mA of output current (VIN = 2.5 V, VOUT = 3.3 V).

Buck-boost regulator achieves high efficiency – [Link]

Running Intel x86 apps on Raspberry Pi 1 and 2

ExaGear Desktop is virtualization solution which opens up a host of new possibilities for running apps across platforms. ExaGear Desktop makes it possible to run Intel x86 application on ARM-based devices, and is targeted to individuals running ARM-based Mini PCs and to businesses deploying ARM-based devices to cut costs. For example you can run Skype on ARM devices (youtube; https://youtu.be/4GUP27TJ5w4). Moreover you can run x86 Windows applications on ARM-based devices by installing Wine.

ExaGear Desktop also boasts outstanding performance specs – in tests it runs 5 times faster than Qemu.

Running Intel x86 apps on Raspberry Pi 1 and 2  – [Link]

Fully reprogrammable optical chip developed


by Graham Pitcher @ newelectronics.co.uk:

Researchers from the University of Bristol and NTT in Japan have developed an optical chip that can process photons in an infinite number of ways. According to the team, the fully reprogrammable chip marks a ‘new era of research’ for scientists and engineers at the cutting edge of quantum technologies. Dr Anthony Laing, who led the project, said: “A whole field of research has essentially been put onto a single optical chip that is easily controlled. The implications of the work go beyond the huge resource savings. Now anybody can run their own experiments with photons, much like they operate any other piece of software on a computer. They no longer need to convince a physicist to … painstakingly build and conduct a new experiment.”

Fully reprogrammable optical chip developed – [Link]

Arduino playing the melody with the Sd card


by sezgingul @ instructables.com:

This project is in SD card loaded stolen melody is provided by command sent from the serial monitor.
If you want to add the application var.siz 6-melody melody melody file must be the same as the name of the specified code name.

The components are used:

Arduino UNO, SD card reader, speakerphone

Arduino playing the melody with the Sd card – [Link]

Arduino Radar Tutorial: Fading an LED With My Breath


by build-electronic-circuits.com:

I built this Arduino radar project, where I control the brightness of an LED with my breath. In this tutorial, I will show you exactly how to do it.

It was an experiment to get the XeThru radar to work with Arduino. I plan to expand on this later, and build more useful applications.

And I will share with you how to connect the hardware, and how to create the Arduino code.

Arduino Radar Tutorial: Fading an LED With My Breath – [Link]


Geiger counter with SBM20 tube


by weirdlab.fr:

I “rebuild” my Geiger counter, the SBM-20 tube was initially inside the box, i have put this one inside a 32mm diam plastic tube, for more convenience, wired through a XLR3 cable. This counter is from “Electronique-Pratique” n°368, a french electronic magazine. Shem, pcb, and PIC hex & C source code available.

Geiger counter with SBM20 tube – [Link]

Basics of Phase Dots on Transformer Windings

This video describes what the “phase dots” are that you often see adjacent to windings of a transformer. It discusses how these dots are used in certain circuits to establish a desired phase relationship between the signals on the various windings. A couple of tips are given regarding how to determine the phasing relationship on homebrew transformers. Finally, measurements are made with an oscilloscope on a trifilar wound transformer to see the phase relationship between the signals on each of the windings with respect to the phasing dots.

Basics of Phase Dots on Transformer Windings – [Link]

Analog Ultrasound Range Finder


by netzener @ instructables.com:

When I started my career in control systems I was fascinated with the many different ways that machines could be interfaced to the environment they operated in. Limit switches (electrical and optical), encoders, resolvers, strain gauges, thermocouples… the control system engineer had a long list of sensors to choose from. And the list has grown even longer following successful innovations in micro machining.

Analog Ultrasound Range Finder – [Link]

UT204 is able to measure DC current and also True RMS


Clamp multimeter UT204 measures reliably even in real conditions of nowadays mains supplies and for an affordable price moreover.

UT204 from company UNI-Trend is a near relative to the UT203. multimeter. Already UT203 provides a lot of user comfort and a very pleasant feature – measuring of a DC current without interrupting a measured circuit. However UT204 is different from its “weaker” brother in one essential thing – it enable measuring of a true RMS value of alternating signals (TRMS).

As we know, usual multimeters usually deploy a simple rectifier and an RC cell and they´re calibrated to show an effective value of AC voltage – supposing an ideally sinusoidal shape of a measured variable.

In many cases, a non-TRMS multimeter is fully sufficient, but still more frequently we meet devices, which by their power consumption significantly deform originally sinusoidal shape of a mains line voltage. A vast majority of new devices is equipped with switch-mode power supplies deforming a sinusoid, as they draw current for charging of input capacitors mainly on a top of a sinusoid. This situation is partially better at power supplies with a power factor correction (PFC), but even in these cases it´s never an ideal load. At any difference from an ideal sinusoid the accuracy of a common meter significantly drops down and the error can exceed tens of percents. Similar situation is also at various DC/AC inverters (for example 12VDC/230VAC), whose output is usually only an approximated sinus.  

That´s why if exact measurement matters to us, it´s more certain to measure by a device equipped by a TRMS measurement. There are many types with this function on the market, and in a segment of clamp multimeters it´s for example the above mentioned UT204, which moreover offers a lot of other functionality for an excellent price.

Detailed information and comparison of UT203/ UT204 will provide you the UT204 datasheet and the UT204 datasheet and UT203-204 user guide. We keep Uni Trend UT204 as a standard – immediately available item.

UT204 is able to measure DC current and also True RMS – [Link]