background preloader


Facebook Twitter

Quadrifilar helicoidal antenna - Javascript on-line calculator. This calculator generates a lot of data!

Quadrifilar helicoidal antenna - Javascript on-line calculator

Take care in the use of the information in order not to make mistakes... Here's a little explanation: Design frequency Evident? Number of turns (twist) What's the twist of the antenna? Length of one turn. DIY Sous Vide Cooker with Feedback Control. Sous-vide cooking involves cooking food in sealed plastic bags inside a temperature controlled water bath.

DIY Sous Vide Cooker with Feedback Control

It's a technique that's been around for a few decades, but is just beginning to be popular in the home kitchen. We decided to give it a try by using a NerdKits microcontroller kit plus some items from our local Wal-mart and Home Depot to construct a sous vide cooker. The result is tasty food with textures and consistencies that are simply unachieveable by conventional cooking techniques! Normal cooking techniques, like heating in a pan or oven, rely on heating the outside surface of food via convection or conduction. That heat must then travel to the center of the food via conduction. In contrast, sous vide cooks the food for a long time at the final desired temperature. Click any photo to enlarge: Warning: There are food safety issues associated with low-temperature cooking. How to Make a Negative Ion air ionizer. NYC Resistor. Converting Cordless To Lithium Li-Po. "Spaghetti" IP Cam / Arduino Motion Detect Sprinkler.

Posted by Phil Tucker on June 17, 2012 After a neighbourhood dog decided my front lawn was a fantastic place to poop on and his owners decided that they don’t care for bylaws I set upon finding a solution.

"Spaghetti" IP Cam / Arduino Motion Detect Sprinkler

Sure you could try cayenne pepper, mothballs, ammonia or even marking your own territory (take that!) But I already had an IP camera monitoring my front yard for security purposes, so I figured I’d just hook up an Arduino and a sprinkler valve. This yard defense solution has two added benefits, it keeps my lawn healthy (I can set up timed watering through this system) and it sends offending dogs home stinkin’ wet. From me having to shovel dookie off my lawn to negligent owners having to deal with wet dog — perfect. How to Build an Inexpensive Seismometer - make seismograph kit. New <em>Daybreak</em> AT&T commissioned short film features Nikola Tesla. Daybreak film segment featuring a model of Tesla'sWardenclyffe Tower Joe Kinney, Senior Project Engineer of the New Yorker Hotel, contacted me recently to inform me of a new short film featuring Nikola Tesla.

New <em>Daybreak</em> AT&T commissioned short film features Nikola Tesla

The film was produced by Ridley Scott Associates and was commissioned by AT&T to promote their mobile technology. The plot of the story revolves around the main character's attempt to unravel the mysterious death of his father who was on the verge of discovering the secrets of Tesla's wireless power transmission. The film is action-packed and very interesting. LCD monitor repair. I have noticed that many people find my blog when looking for monitor repair ideas. So here is another one of my ideas for monitor repair. I have in the past fixed laptops by retrofitting them with LED's. The problem with this monitor is that the power supply for the vacuum tube back lighting dies.

Electric Clothing. Solar Panel Setup around $100. 12V BoostPack. Replaces auto battery. Works great! MPPT Lead Acid Battery Charger Circuit. The post explains a simple yet effective MPPT lead acid battery charger circuit using the IC bq2031 from TEXAS INSTRUMENTS.

MPPT Lead Acid Battery Charger Circuit

Abstract This practical application article is for the individuals who may be developing an MPPT-based lead acid battery charger with the aid of bq2031 battery charger. This article includes a structural format for charging a 12-A-hr lead acid battery employing MPPT (maximum power point tracking) for improving charging efficiency for photovoltaic applications. Introduction The easiest procedure for charging a battery from a solar panel systems could be to hook up the battery straight to the solar panel, however this may not the most effective technique. Solar 102 - Power Calculation. An Inside Look at the Insanely Complex Formula 1 Steering Wheel. The steering wheel of the Sauber C33 Formula 1.

An Inside Look at the Insanely Complex Formula 1 Steering Wheel

Everything a driver might need to do, and every bit of information he might need to know, is literally at his fingers. Photo: nph / Dieter Mathis/picture-alliance/dpa/AP Images The modern Formula 1 car is among the most amazing machines ever made. And when you’re going wheel-to-wheel with someone like four-time world champ Sebastian Vettel at 180 mph, you can’t take a hand off the wheel to do, well, anything.

Every task a driver might need to do, every bit of information he might need to know, is quite literally at his fingertips. The modern Formula 1 steering wheel is, therefore, the most amazing ever made. That’s because an F1 car has dozens of parameters that can be adjusted on the fly, but only by the driver. The PCU-8D LCD screen, made by McLaren Electronics, is 4.3 inches wide with a resolution of 480 x 272 pixels. AmericanRadioHistory.Com - Documenting the History of Radio TV and FM broadcasting. Batteriser is a $2.50 gadget that extends alkaline battery life 800%

Bob Roohparvar tells a killer story of industrial espionage.

Batteriser is a $2.50 gadget that extends alkaline battery life 800%

He says the robbery occurred at his Batteroo office space in a sprawling Silicon Valley office park. The target was intellectual property surrounding Batteriser, a simple metal sleeve that promises to give consumers up to eight times more life from their disposable batteries, AAA through D. batteroo The crooks clearly knew the building layout, and exactly what they were looking for—namely, a breakthrough technology that, if legit, could blow the lid off an alkaline battery industry that’s worth $3.4 billion annually in the US alone.