Jan Rychter @ jan.rychter.com designed his own Nixie power supply that except the high voltage has two voltage outputs to power the logic circuitry, he writes:
This project is a HVPSU (High-Voltage Power Supply) that generates up to 220V from a 12V input. In addition to that, it also provides 2*Vout (so, up to 440V, for dekatrons), and two outputs for powering digital logic: 5V and 3.3V. The primary HV boost circuit reaches 88% efficiency when going from 12V to 185V at 55mA, with a 3% output ripple.
I designed it because I couldn’t find anything that would make sense for my Nixie projects. There are plenty of tiny power supply modules available on eBay, but most of them end up being impractical: no 3.3V (for my microcontroller) and 5V (for my 74141 nixie drivers), no mounting holes, no >400V output for powering dekatrons. Some supplies make a token gesture towards practicality by sticking a 7805 on the same board, but you quickly find out that the current draw of 6×74141 is enough to require a large heat sink on a 12V-powered 7805 (one 74141 consumes 12.5mA!). This means that instead of a single-board power supply you end up routing your input power all over the place, implementing your power supply in several places.
High Voltage Power Supply for Nixie Tube Projects - [Link]
Alan Parekh @ hackedgadgets.com bought a photo-switch on ebay and takes a look inside. He writes:
I spotted this photoswitch on eBay and had to take a look at the guts (search photoswitch if the link doesn’t work since eBay links go stale after a short time). I now see that the same unit is sold in multiple variations which are 24V and 220V. Not sure I would feel safe with 220 on this thing though. I am curious if the 10 ohm resistor is the only difference between the versions. If someone has one of the other versions leave a comment to let us know what the difference is. These are selling for $3.39 which included free shipping from China to Canada! Hard to believe how tilted the scales are here, I wouldn’t be able to ship this within my city for $3.39. The unit is powered from 12 volts AC or DC, it also switches the same power to the third output wire when activated. The circuit is using a 555 for operation. When the photocell goes from light to complete darkness the relay activates in 3 or 4 seconds. You can view full resolution images here.
eBay Photoswitch Teardown - [Link]
Raj @ embedded-lab.com writes:
This instructable describes in detail the setting up a full-featured weather station that records air temperature, relative humidity, and ground surface temperature right below the weather station. The project uses Phidgets SBC3 computer board, which is powered by an 18-watt solar power along with a battery backup.
PhidgetSBC3 based solar-powered weather station - [Link]
The eye-strain implications alone are staggering.
To promote the upcoming Exceptional Hardware Software Meeting (EHSM) in Hamburg, Germany, a team of DIY artists and scientists has etched the world’s smallest comic strip on a single human hair.
Titled “Juana Knits The Planet,” the strip was created by German artist Claudia Puhlfurst, then carved into the hair using a process called focused ion beam (FIB) etching. “A very sharp and high-speed jet of matter is produced and directed towards the hair to etch it — similar to a fine laser beam,” according to the project’s YouTube page.
Each of the strip’s 12 frames measures in at around 25 micrometers. A micrometer, or micron, is one millionth of a meter. A typical human hair is anywhere from 20 to 200 microns in width.
The second annual EHSM event bills itself as a meeting of international makers, hackers, scientists and engineers aiming to deliver on the “third industrial revolution.” The rest of the conference looks pretty trippy, too.
Among the presentations: electron beam welding, quantum cryptography and the interesting things that happen when molten glass, heated to 1,260 degrees Celcius, hits water. I’ve always been curious about that.
World’s Smallest Comic Strip Etched Onto Human Hair - [Link]
Alan Parekh of Hacked Gadgets writes:
Thanks to Circuit Specialists for sending in this 3 chanel power supply. The Hantek PPS 2320A sure packs in a ton of features for the price. The video below goes through the unboxing of the power supply and a quick run through its features. Overall it functions quite well, there are a few questions that need some clarification. I will have a look through the manual and reach out to the guys over at Circuit Specialists if I can’t find the answers.
Hantek PPS 2320A review - [Link]
By Tahar Allag, Wenjia Liu:
Cell phones are a good example of how functionality and performance have both increased significantly in portable devices over the last few decades. They have become more complex and can do many basic tasks as well as any computer. The extra functionality that has transitioned the smartphone from a phone-call-only device to a multipurpose portable device, which makes it more power hungry than ever before.
The internal battery pack is the main source of storing and delivering power to portable-device circuitry. Batterycharger ICs are responsible for charging the battery pack safely and efficiently. They must also control the power delivery to the system to maintain normal operation while plugged in to wall power. The battery pack is required to store a large amount of energy and be charged in a short amount of time without sacrificing weight and volume. The increased charge and discharge currents, as well as the smaller physical size, make the packs vulnerable to physical and thermal stresses. Therefore, battery chargers are no longer required to perform just as a simple standalone charger
AppNote: Battery charging considerations for high-power portabledevices - [Link]
Designers of rechargeable battery-powered equipment want a charger that minimizes charge time with maximum charge current by maximizing the power taken from the supply without collapsing the supply. Resistances between the supply and the battery present a challenge. This article explains how to design the charging circuit to achieve the maximum power from the adapter despite the undesired resistances between the supply and battery.
AppNote: Extract maximum power from the supply when charging a battery - [Link]
By Boris Landoni @ open-electronics.org:
By coupling a standard NMEA GPS receiver and an Arduino board we created a super simple and effective Arduino GPS logger. This device allows you to trace the route taken by a person or vehicle (or any other moving object) by simply doing a periodic caching of location points coming from the GPS unit. As the logger saves the list of records (containing data on recorded positions) on a microSD memory card, you can then move the data onto your computer and keep track of your trip. You can use tracked data to help project such as OpenStreetMap to grow and include new areas (www.openstreetmap.org).
An Arduino powered, easily extendable GPS Datalogger - [Link]
We bring you basic useful accessory of every development and testing workplace – measuring and testing leads in the best available quality.
Whether you measure daily or only sometimes, probably you know, how significantly helpful various accessories can be. Or otherwise – how much time can consume unreliable measuring cables or other accessories, when after a long investigation for a mistake in a design you´ll find, that everything is OK, only a measuring cable had a bad contact …
For everyone who has a will and time to assemble measuring tools we have measuring tips, clips, bananas and other accessories from company SKS (Hirschmann-SKS). For those of you, who better prefer ready-made, professionally made measuring cables, we have an elegant solution in a form of the cables themselves, as well as measuring sets. Such cables and sets are especially suitable for professional workplaces and for a mass usage in assembly and testing.
Company SKS is a long time focused for measuring accessories and its products under a mark SKS-Hirschmann are known by their quality and ergonomics. From the wide production portfolio of SKS can be found in our store for example cables with a banana and a socket for a header MALN series), safety measuring leads (MALSW series), measuring leads with bananas on both sides (MLN), measuring leads with measuring tips, as well as measuring sets – PL2600 or PMS series. All measuring leads are highly flexible and with a thick insulation.
For workplaces with a high risk of damage of measuring leads from for example a hot soldering tip or other heat source are an ideal accessory silicone testing leads series MLS SIL. A „complementary” but very valued feature of silicone testing leads is also their extreme flexibility resulting in a very comfortable work. These leads we´re able to provide you upon order. Detailed information about measuring and testing equipment can be found in the Hirschmann SKS catalogue.
SKS testing lead will be your favorites - [Link]
by Kalle Hyvönen:
I saw a cool app-note from Maxim that described a gamma-photon detector which used a regular PIN-diode as a sensor. The actual circuit looked simple enough so I decided build it, you can never have too many measurement instruments right?
The detector in itself is pretty simple, just some op-amps and a comparator. I decided to build it with all the bells and whistles so I included a digital potentiometer so you can adjust the reference voltage to the comparator via an SPI-bus. I also used a 5V reference shunt as the reference for the op-amps and the comparator to keep the circuits behaviour more consistent. I didn’t have any adjustable capacitors with an SPI bus so I decided against using one (instead of C4, changing the capacitance changes the gain).
A radiation detector with a solid-state PIN-diode sensor - [Link]