Testing audio-noise-reduction circuits, PLLs (phase-locked loops), and audio-frequency filters may require a noisy sine wave. Generate noisy sine waves with a sound card article tells that using a typical computer sound card, free software, and an external amplifier circuit, you can create a noisy sine wave. So a sound card, software, and an amplifier circuit →
Audiophiles seem to revel in minor controversies – vinyl vs CD’s, tubes versus solid state, capacitor, wires, magic dots… and negative feedback. At one extreme (“objectivists” and engineers), the position is that “feedback makes amplifiers perfect”. At the other extreme (“subjectivists”) usually claim that “feedback is a menacing succubus that sucks the life out of →
Using existing triac controllers and wiring offers a number of challenges for LED lighting. To maximize the success and adoption of solid-state lighting for retrofit lamps, the LED lamps should be capable of dimming when used with existing controllers and wiring. Lighting designs with flicker-free LED dimming article explores the typical TRIAC dimmer, some of →
Facebook Open Sources Its Servers and Data Centers. Facebook has shared many details of its new server and data center design on Building Efficient Data Centers with the Open Compute Project article and project. Open Compute Project effort will bring this web scale computing to the masses. The new data center is designed for AMD →
Linux is celebrating its 20th anniversary this year. Video and festival competitions can be found on Linux Foundation celebrating 20 years of Linux pages. The History of Linux began in 1991 with the commencement of a personal project by a Finnish student, Linus Torvalds, to create a new operating system kernel. Ari Lemmke named the →
I getting certification for your software far too challenging? This is a brilliant idea for a new application certification program The “Works on My Machine” Certification Program. Participating in this innovative new application certification program is as simple as pressing the F5 key on your keyboard. Just few easy steps… Brand your app with your →
Google Labs Page Speed Online analyzes the content of a web page, then generates suggestions to make that page faster. Page Speed Online is available from any browser, at any time. This allows website owners to get immediate access to Page Speed performance suggestions. You can also get Page Speed suggestions customized for the mobile →
Selenium IDE is a Firefox add-on that records clicks, typing, and other actions to make a test, which you can play back in the browser. It allows you to easily and quickly record and play back tests in the actual environment that they will run. Selenium IDE is not only recording tool: it is a →
Power-supply circuit operates from USB port article mentions some useful points on using USB connector as power source as well as gives an useful circuit diagram. You can use a USB port to power an external circuit. Even one without any USB functionality in it. Every PC has a USB (Universal Serial Bus) port that →
You-Should not Reboot Unix Servers without a good reason. Rebooting Windows boxes when something is not right is a way of life. Article When in doubt, reboot? Not Unix boxes explains why you should almost never reboot a Unix server. Server reboots should be rare — very rare. In many cases, it’s extremely important not →