You may know what the inside of a PC looks like, but what about the parts which make up your PC components? Your Hardware Exposed! 22 PC Parts Bare All article has pictures what is inside hard drives, keyboards, soundcards, and a plethora of other PC hardware. Just to see what makes them tick.
Open Source Licenses document Zack Rusin published at KDE web site gives a good overview of different open source licenses. Here you can find the most important details of the most commonly used open source licenses in a very compact easy to understand format.
3D Projection on buildings video at http://www.loodzwaar.com/2009/07/21/3d-projection-media/ shows amazing visuals that can be made by projecting 3D graphics to buildings. Take a look at this video.
Power and Grounding for Audio and Audio/Video Systems – A White Paper for the Real World is a “White Paper” that attempts to cut through the confusion and set out a collection of good engineering practice that is both safe and effective. This 37 page technical document is worth to read for everybody who works with electricity and/or audio/video systems. it gives a good introduction to power system architectures used in North America and gives also brief introduction to systems used in Europe. The section “Some Useful Troubleshooting Tools” gives ideas what tools to use to troubleshoot the problems.
More than a year ago I was approached by an independent filmmaker about light dimmers. The problem fo them was how to get affordable light dimmers to control the film lighting. I was told that many independent non-commmercial filmmakers use a HarborFreight router speed control to dim the lights used for moviemaking. The reason is that they are are cheaper and far heavier (15A) than building our own from a 600W house lights dimmer. The problem with these router speed control devices is that they do not dim down enough to turn the lights off. They also don’t quite go to full brightness but that is a minor problem as they have a switch that bypasses the electronics and provides full power.
After some discussion I got one of these units mailed to me to see if there is a way to modify those to work as better light dimmer.First thing I did was to open the device to see how it was built out. Based on what I saw the circuit was pretty close to a traditional light dimmer. And there seemed to be also some adjustment trimmer for some adjustments. Looked promising.
The nest task was to test the device. The problem that those are designed to operate 110-120V AC 60 Hz power has a slight problem to me. In Finland the mains power is 230V AC 50 Hz. Getting real 120V 60Hz power and finding 120V AC light bulbs is hard here where I live. I got one 120V lamp with the router speed control device so I had suitable lamp. Getting real 60 Hz power would involve some expensive power converter or using 12V to 120V AC true sinewave inverter or something similar that I did not have at the moment. So I decided to do my first testing with 110V 50Hz power that I get easily with a suitable voltage conversion transformer (I used fully isolating transformer for safety).
I did some testing. I found that the controller trimmer potentiometer controls how dim the output can go. I was able to get lamp very dim. Here is the picture of the dimmer electronics with a well insulated screwdriver adjusting the trimmer (there is a hole on the circuit board that gives access to the trimmer). Well insulated screwdriver and isolation transformer powering the whole circuit makes it possible to do ajustments with live circuit pretty safely when you know what you are doing. I mailed the results back to person who sent me the router speed control and he tested the results with real 60 Hz power (they worked).
The adjustment instructions: Set the potentiometer lowest setting. Then adjust the trimmer so that you get as dim light as possible without noticeable side effects. When you set the trimmer to too low setting, turning potentiometer will cause the output to be completely off (lap turns off). When dimmer reaches this full iff state, the dimmer potentiometer need to be turned quite much (one third or one fouth) until the light turns back on, quite bright already. The ideal setting I think would be that the lowest dimmer potentimeter setting would just set the bulb to be just barely on (lamp filament dark red and does not make much light), so you have always full control range from it to full setting without problems.
In this way a relatively cheap router speed control device is converted to a relatively inexpensive high power light dimmer.
Learn how to roll audio cables to avoid tangling. There are several good videos on Internet which tech you how to do that. How to Set Up PA Systems : How to Roll Audio Cables video gives you instructions how to roll audio cables to avoid tangling and tips on PA sound system setup.V1 Cable Wrap is a classic tutorial video that teached me how to properly wrap the audio and video cables easily.Cable Wrangling video teaches you how to properly wrap all kinds of cables and pack microphones.
Ryan Joyce – Arena Show Time Lapse is a video that shows how a magic show is built up. The video starts from unloding the truck and ends with the images from the show. This is how arena shows are built professionally.
Resistance soldering is a soldering method that sometimes useful for hobby work. In this soldering methid an electrical current is flowed through one work piece, the joint and then the other work piece. Current through a resistances on the way generates heat. Most heat is normally generated on the joint because the resistance there is typically the highest.
Resistance soldering web page describes the technology in details. Resistancesoldering.com/ tells that resistance soldering can work also on some PCB work and similar applications. Resistance soldering is claimed to be good for soldering RF connectors, for example connectors on semi-rigid bases and central contacts on coaxial connectors. The soldering operation consists of clamping the parts to be assembled and adding a solder alloy. The heating process starts as soon as the foot pedal is activated and the temperature rises to the set temperature point. Look the video tutorial on soldering RF connector with resistance soldering.
According to Resistance Soldering Set document a resistance soldering set consists of a transformer that supplies 3 or 6 volts at a high current to stainless steel or carbon tips. The transformer is turned ON by a foot switch and OFF by an electronic timer (up to few seconds time). Since the soldering tips are hot only during the brief period of actual soldering, burning of wire insulation and melting of connector inserts are greatly reduced.
Build your own resistance solderer tells you how you can make your own resistance soldering iron with minimal investment. Resistance Soldering Unit is another page that gives instructions to build your own resistance soldering iron.
Google (GOOG) has begun operating a data center in Belgium that has no chillers to support its cooling systems. Google’s Chiller-less Data Center is an article that describes Google elimination of chillers in its data center in Belgium. The facility relies entirely on free air cooling. The maximum temperature in Brussels during summer is lower than the temperature Google maintains their data centers. If it for some strange reason gets too hot, Google shuts down the center and shifts the workload elsewhere. This approach makes local weather an issue in network management. The ability to seamlessly shift workloads between data centers also creates intriguing energy management possibilities.
EDN blog articlwe HDMI cables for $2 or $600? mentions article Why are HDMI cables so expensive?. In this article product researchers find little difference between a $10 and a $140 HDMI cable. The result was that the expensive cables may be made with better materials, but they don�t perform digital transmission any better than the cheap cables. At least when talking about a short cable of few feet then I don’t see any reason to pay very much for it. If your local store does not sell reasonably priced HDMI cables, then go to some other store or order on-line. Some shops seem to charge absolutely ridiculous prices for HDMI cables knowing full well that they are taking advantage of people who don�t know any better.
Another thing worth to read at HDMI cables for $2 or $600? is a story on very expensive “audiophile” cables that were sold with “story” that adding DC bias to audio cable helped sound. The dc bias to the cable was added using a 9-volt battery. It of course was adjustable ($0.05 pot) so that the lunatic fringe audiophile community could have an infinite level of adjustment and an associate infinite collective of opinions as to what was the perfect setting – pure marketing genius. Good story and “market factors” seem to sell cheap products at high price.
