radiant point near the star Castor in the Gemini constellation. An interesting project on
FM Radio Detection of Meteors has a fun discussion on a 10th grade science project.
If you just want to look at the sky, there will be a lunar eclipse on 21-Dec.
Recycle Christmas Light Packaging
From Radio World
Are you buying some of the new LED lights for your holiday decorations? Recycle the plastic holders that some lights are packaged with. It can be used to organize and hang your test leads.
Use a heat gun to warm the plastic tabs and bend them over to form mounting tabs.
Tower Climbing
This helmut cam video provides a first person perspective of an extreme transmission tower climb.
Operating In a DX Country
From Multiple Sources
We often think about needing to get some type of license if we wish to operate in an area not under the jurisdiction of the FCC. The US has recirocal agreements with some contries, such as Canada. US Amateur Radio operators can also operate in some European countries as part of the CEPT licensing requirements. The International Amateur Radio Permit (IARP) allows for operation in certain countries of the Americas.
Boeing SkyTerra Satellite
From Multiple Sources
Boeing is receiving on-orbit signals from LightSquared's SkyTerra 1 following the satellite's launch on 14-Nov. The 6-ton satellite has a mesh screen reflector that is 72 feet across. It will be part of a space-based network providing mobile broadband wireless services utilizing both ground-based networks as well as satellite coverage. SkyTerra 2 is expected to be launched in 2012 with a system build-out by 2015.
Light-Fi
From Wired
Wi-Fi signals are often associated with RF. As the demand for spectrum increases, conventional Wi-Fi can have limited bandwidth and increased interference. Researchers are experimenting with using visible light as a data conduit. Flickering lights at a high frequency can generate the signal in a room without being noticable by the human eye. Although the data rate would be slower, interference should be diminished because the light will not penetrate walls. By using blue LEDs, the researchers were able to achieve 230 megabits per second.
Fading Past
From Multiple Sources
We know a magnetized surface will slowly be depleted. One of the expected benefits of optical technology (i.e., CDs) was a long life for archiving purposes. The original CDs were physically stamped with microscopic holes. Recordable CDs (CD-R) use a colored dye that changes color when exposed. The life of the data on a CD-R is partially dependent on the type of dye used to fabricate the CD-R.
You may be able to determine the type of dye by the color of the surface of the CD. PhthaloCyanine is transparent, but appears golden due to the reflection layer. This material is supposed to be the most durable. Azo dye CD-Rs are dark blue in color. It is considered the most resistant dye against UV rays. Cyanine pigment will generally appear to be green. Cyanine is considered to be the least expensive and least durable. Newer cyanine inlcudes a silver reflection layer. The disc will appear blue and have alonger life. Some manufacturers altered the coloring or reflective coating to disguise the actual coqating being used, so color cannot be used as the only consideration for determining the type of dye on a CD-R.
Memristors
From Cosmic Log
Moore’s Law was first defined in 1965. as a general rule to estimate the number of transistors placed on an integrated circuit. The rule stated that the number of transistors that could be placed on an integrated ciruit would double every two years. Memory chips are reaching a limit of density based on current technology. Memory resistors (memristors) are a concept that goes back to the early 1970s. The molecular structure of amaterial is changed by changing the sirection current is passed through the material. The material retains the structure even when the electrical current is removed. The density of memory chips could be increased using memristors rather than the traditional silicon based components. The devices might also allow "instant on" access to data.
Blood Power
From New Scientist
No, this is not something about vampires. Researchers created created tiny microbial fuel cells by encapsulating yeast cells in a flexible capsule. The fuel cells can generate power from a drop of human blood plasma. Using a yeast commonly used in brewing and baking, the yeast metabolises glucose and steals electrons. Hydrogen ions that diffuse out of the yeast cells combine with oxygen to create water. The prototype produces 40 nanowatts of power, which could power some devices.
Lithium-Sulphur Battery
From Science Daily
This new lithium based battery may store and deliver more than three times the power of conventional lithium ion batteries. Sulphur is cheaper than many other materials currently used in lithium batteries. Combining the two chemistries delivers higher energy densities. At the nanoscale level, researchers used a porous carbon family called mesoporous carbon. This type of carbon has a very uniform pore diameter and pore volume. Sulphur fills the pores, exposing an enormous surface area of the active element to carbon and driving the exceptional test results of the new battery.
