Balanced inputs and outputs have been used for many years in professional audio, but profound misconceptions about their operation and effectiveness still survive. Conventional wisdom about them is sometimes wrong. Balanced Line Technology web page gives you a good look at the balanced line technology in audio applications. The balanced line technology is also applicable →
I wrote about EMF measurements and told that for magnetic field measurements I have used Velleman Magnetic Field Detector VTEMF. Velleman describes the product uses: “Detects the harmful electromagnetic fields generated by high voltage cables, computer and television screens, microwave ovens, waterbeds, electric blankets, etc.”. That sounds reasonable. The description continues “Scientists believe that electromagnetic →
An electromagnetic field (also EMF or EM field) is a physical field produced by moving electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. It is one of the four fundamental forces of nature. EMF measurement →
Ethernet is 40 years old. In 1973, Bob Metcalfe sent an internal memo for a LAN design. Ethernet at 40: Its daddy reveals its turbulent youth is a well worth to read article that tells about the youth of Ethernet and why it became the dominant LAN standard. It also tells how much Ethernet owes →
Logic Sniffer Java client is an alternative OLS-client provides a software client for the Open Bench Logic Sniffer logic analyser hardware (that is based on ideas from open source SUMP analyzer). Software works also with SUMP compatible devices and Bus Pirate hardware. When tested with the demonstration data the software seemed to work quite well →
Google now allows web developers to share hosted websites via Google Drive. Google Drive now lets developers share hosted websites by storing HTML, JavaScript, and CSS files article gives you nice instructions how to do that. The basic idea is to upload site files to Google Drive folder and share it a as “Public on →
With all the talk of Internet filtering in Australia and the high cost to implement the filter, an Australian technology distributor has come up with a cheaper solution to the governments Internet filter: The Kogan Portector. That filter in the video did not get into real use. At November 2012 finally Australian federal government has →
My article Signal reference grids in the data center shows that different types of data communication interfaces are classified into susceptibility classes: Data communication interface classification Susceptibility class: Low immunity Interfaces in class: Parallel ports, RS-232 ports, Proprietary back-plane, Video cables Characteristics: Copper cabling with ground referenced signals. Any shift in ground voltage between the →
It is sometimes suggested that a mains power isolation transformer might be used to solve the ground loop problem. It is true, that many times a mains isolation transformer does help, but not always. A system with properly used isolation transformer is still safe, it can be even safer than system without isolation transformer. Remember →
One of the most common direct coupled noise sources is when the ground which is being used for reference or return is not referenced to earth as expected. This is especially prevalent in sensitive high-gain circuits. Grounding and Shielding Existing Equipment – How to effectively minimize EMI issues when best practices are not available is →