Archive for February 2013

Current sensor for multi core cable

There are many ways to measure current. The traditional methods of taking current measurements by inserting a shunt resistor or using a current transformer have the disadvantage of having to break the circuit conductor. For current transformer there are also models that can be installed in place without cutting the cable (more expensive and usually

Enterprise Network Firewall trends

2013 Gartner Magic Quadrant for Enterprise Network Firewalls give a view to current firewall markets: Gartner states, “Advances in threats have driven mainstream firewall demand for next- generation firewall capabilities. Buyers should focus on the quality, not quantity, of the features and the R&D behind them. This market includes mature vendors and new entrants.” Palo

Bad Microvault USB memory

I bought some time ago Key Style Stainless Steel Hot Swapping USB 2.0 Flash Drive – Silver (8GB) hoping to get a nice USB memory that I can include to my keyring. The product got even some good reviews at Dealextreme product page. At first everything looked good. The good things was that this product

Open Source versus Business Models

Network World is running a guest article Open Source Software Licenses versus Business Models by Outercurve Foundation’s technical director Stephen Walli discussing how FOSS license choice can affect a company’s business model. In Open Source Software Licenses versus Business Models article Walli disagrees that a FOSS license dictates the business model or that the business

Battery capacity, price and other details

Selecting the Best Battery for Embedded-System Applications article tells that non-rechargeable (primary) batteries find wide use in mainstream embedded-system applications. This category of batteries includes alkaline devices, which manufacturers typically fabricate using manganese dioxide and zinc powder with a caustic alkali of potassium hydroxide as an electrolyte. The nominal voltage of an alkaline cell is

Event Safety Guides

Safety is important when arranging events. And there are a lot of things to consider to make the event safe for everybody (I know from experience from several event I have been working with). Control Geek blog writes about US Event Safety Alliance Document in Public Review. The Event Safety Alliance is a group of

Crypt WebGL demo

Mozilla announced a new WebGL demo: Crypt Demo. This Crypt Demo is a great example for how far browsers have come and for the cross-platform experiences developers can now create without having to rely on plugins. The demo is written by ACTISKU‘s Anthony Liot. The demo should run in most modern browsers that support WebGL

Understanding grounding, shielding, and guarding

Inadequate shielding and bad grounding are often blamed when measurements are inaccurate, especially in high-impedance applications. Understanding grounding, shielding, and guarding in high-impedance applications article tells tells that in fact, shielding and grounding problems are frequently responsible for measurement errors, but many test system developers aren’t quite sure why. Many measurement errors can be traced

HDMI and ground loops

In my Audio and video signal susceptibility classes I wrote that digital video interfaces like DVI and HDMI can also have ground loop noise problems as they use a combination of balanced and unbalanced signals. Ground loop problem is one very possible source of intermittent problems over long distance in HDMI installations. This article is