Star-quad design is sometimes quite a bit of talked about cable type. When I saw Star-Quad Cables and Double-Blind Testing posting at Controlgeek blog I decided that it would be a good idea to write something about them. Several companies use a quad configuration in their balanced cables instead of a twisted pair; Canare calls →
Grounding Complications is a very informative 28 slide set from PowerCET. It worth to read for everybody working with ground loops and electrical wiring. The slide set concentrates on following issues: Sensitive Equipment, Isolated grounding and Supplemental grounds. The slide set tells about wiring practices in use in USA, but there are also general information →
Everybody seems to be saying that you can’t charge Apple devices with normal USB power supplies. You need a special power supply from Apple or approved by Apple. I saw this kind of discussion at slashdot some time ago. Usually, device makers need to sign a confidentially agreement with Apple if they want to say →
Allen Avionics Audio Isolation Transformers page describes the typical ground loop problem situation with the following drawing: If you want to do the ground loop elimination in audio path, you have to cut the galvanic connection but pass the whole audio range. The simplest and most common way to do the isolation is use audio →
The monkeys got my multimeter article has an interesting video that shows a really crappy design aspect of this IDEAL multimeter. Was this caused by a design or specification problem is hard to say. Very probably, for an economy DMM like this one, the ability to operate the buttons without rear support (i.e. your own →
My Time Domain Reflectometer (TDR) circuit is now available in kit form. Far Circuits has made a TDR kit that consists of circuit board and components. The Far Circuits version is a slightly modified circuits, the modification is that the circuit board has a 5V regulator IC in it. With that regulator the circuit power →
I has been very hot and dry in Finland. Some kind of irrigation system or manual irrigation seems to be necessary to keep the plants happy. Livehacker reports on an interesting Build an Arduino-Powered, Tweeting, Self-Watering Garden System. It’s extremely simple. And, not only will the Arduino water the soil when it starts to get →
Chipshow’s LED tube page gives some views what LED tubes look like. As you can see there are many LEDs inside a LED tube. The most economical way to run sich LEDs from mains power is to connect many LEDs in series and then use some current limiting circuit to set the drive current right →
The idea if replacing fluorescent light bulbs with LEDs seems to become popular. There are different kind of products made for that purpose. LED bulbs utilizes large arrays of high power LEDs to provide up to provide light. They are at best an economical way to replace commonly used fluorescent tubes. Since introducing LED based →
Toolkit: A Look at the Gear That Experts Use to Spy on Spies is an interesting article. Kevin Murray heads one of the most sophisticated surveillance-detection firms according to the article. Wired asked Murray about the bevy of gizmos he and his staff use to sniff out corporate espionage. →