by limpkin @ limpkin.fr:
During the month of July I was visiting Beijing and had an extra 10 days to spare. What to do? Well it took me less than a few minutes to decide to go the wonderful city that is Shenzhen…
Video Series – Touring Factories in Shenzhen - [Link]
by Russell Barnes @ www.raspi.today
The Director of Hardware at the Raspberry Pi Foundation, James Adams, walks us through the making of the new and improved Model B+ and more…
While he was a chip designer at Broadcom, James Adams ran the design team that created the 3D graphics engine that went on to feature in the Raspberry Pi, arguably the Pi’s strongest asset.
Later he moved to a tech startup called Argon Design that was created by the same man behind the original company that Broadcom bought many years ago for its multimedia technology. The 4th generation of that very chip also features in the Raspberry Pi, so Adams was already well versed with its capabilities long before joining the Foundation in February 2013.
The making of the Raspberry Pi Model B+ - [Link]
by dreded @ dredx.com:
In my home I have a fairly long hallway that has light switches at either end but 99% of the time we enter the hallway from the middle where there is no switch. So I decided I needed to do something about this as walking down a dark hallway all the time was annoying.
I have seen a fair number of people use an arduino or even a standalone ATTiny85 with a El cheapo HC-SR501 which can be found on ebay for about $1.25 each and I find these things work fantastic, they have an excellent range and detection spread.
Motion activated lighting without a Micro-Controller - [Link]
Did you know you can use your frequency counter to detect gravity? You’ve likely done it before and you didn’t even know it!
Dave demonstrates the phenomenon of 2g-tipover on quartz crystal oscillators in an Agilent 53131A frequency counter.
EEVblog #646 – Gravity Detection Using A Frequency Counter! - [Link]
Most of the work that I have done in the past with vacuum tube and solid state electronics has been repair. So, I have ventured into the realm building. This is actually my second build (I’m still getting the bugs out of the first attempt) but I have applied all that I learned from mistakes to this build. Building from scratch is nothing like repairing. It takes time, a lot of thought and reasoning go into a build no matter how simple it may look.
6v6 Stereo Amplifier - [Link]
Analysis of the bipolar transistor amplifier at low-frequency is relatively easy, and several calculators exist online that do a good job. For high-frequency operation, there are fewer references available. For my projects, I like to build a reference spreadhseet where everything is in one place. This allows me more flexibility in optimizing the circuit, and is much faster than simulating with LTSpice or similar package. Furthermore, constructing such a tool is a great way of gaining more insight into how the circuit works, and how each of the parameters affects performance.
Common-Emitter and Common-Collector Transistor Amplifier Calculator for High-frequency Operation - [Link]
by Boris Landoni:
This robot will mow the grass of your garden, staying within a defined area, avoiding all obstacles and working in complete autonomy, automatically charging itself with a solar panel.
In this post we present a robotic lawn mower, powered with solar energy and able to operate just with the clean energy from the sun; this one is a great difference from the commercial projects having a robot in need of a charging station connected to the electrical grid.
A Robotic lawn mower powered by Solar Energy with an Arduino heart - [Link]
A primer app note(PDF) on silicon transient voltage suppressors by Microsemi.
Silicon transient voltage suppressors (TVSs) are clamping devices that limit voltage spikes by low impedance avalanche breakdown of a rugged silicon pn jucntion. They are used to protect sensitive components from electrical overstress such as that caused by induced lightning, inductive load switching and electrostatic discharge.
App note: What is a silicon transient voltage suppressor and how does it work - [Link]
An application note from Texas Instruments, white LED driver with digital and PWM brightness control (PDF!):
With a 40-V rated integrated switch FET, the TPS61160/1 is a boost converter that drives LEDs in series. The boost converter runs at 600kHz fixed switching frequency to reduce output ripple, improve conversion efficiency, and allows for the use of small external components.
The default white LED current is set with the external sensor resistor Rset, and the feedback voltage is regulated to 200mV, as shown in the typical application. During the operation, the LED current can be controlled using the 1-wire digital interface ( Easyscale™ protocol) through the CTRL pin.
App note: White LED driver with digital and PWM brightness control - [Link]
High efficiency, low standby power consumption and a power reserve, all this can be gained with a new adapter from our portfolio.
Minwa NR120P150PGS/E+ is in fact an “ordinary“ adapter with a fixed output voltage 12VDC/1500 mA. But it´s worth to mention, that it meets everything, what we usually require from a modern mains adapter:
- modern design (SMPS)
- high efficiency
- low standby power consumption (<0.3W)
- meets all latest regulations – EuP2, ErP,…
And finally a bonus – outstanding price. Adapters from company Minwa are in general always price-affordable, but here it is even more obvious. When we compare a one level weaker adapter NK120P100PGS/E+ (12V/1000 mA) with NR120P150PGS/E+ we´ll find, that for the price higher +14% (already at purchase of one piece) we´ll gain +50% power. So if you have a device requiring up to 1.5A current, or you use a 1A adapter at almost 100% and you want to gain some power reserve and probably a longer lifetime of an adapter, you can do so with minimum expenses.
Plus 50% of power for a scant one Euro? - [Link]