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Cool Pic Archive #15

Cool Pic Archive Pages

| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 |

These images have been chosen for their uniqueness. Subject matter ranges from historic events, to really cool phenomena in science and engineering, to relevant place, to ingenious contraptions, to interesting products (which now has its own dedicated Featured Product category).

RF Cafe: Duracell Ultra 9V Battery Disassembled to Show the Six AAAA CellsHave you ever wondered what is inside the familiar 9V battery? I used a small screwdriver and a pair of pliers to remove the outer metal case. If you did not already know, you might be surprised to find that there are six AAAA cells are connected in series.

11-10-2008

RF Cafe - World's first atomic wrist watchThis might just be the world's first atomic wrist watch. It does not need the 60 kHz signal from Boulder, Colorado, to maintain its accuracy. Some work is still needed for mass production. I did not see a lady's version advertised on their website. (thanks to Kevin A. for the link)

10-13-2008

RF Cafe Cool Pic: Transistors in SpaceNASA is testing a new breed of radiation-resistant transistors for space apps. Those shown here are attached to the International Space Station for evaluation. High-energy protons, neutrons, and ions streaming through space pose an extreme threat to critical electronics for both Earth-orbiting and interplanetary missions. The usual silicon dioxide insulating dielectric is replaced by an organic compound, which assembles itself from three chemical solutions into a 15‑nanometer-thick layer. The organic dielectric is more radiation-proof than silicon dioxide because it conducts holes well.

9-15-2008

GPS-generated self portrait - click for details, and a surpriseUsing a briefcase-borne GPS unit in a specially consigned DHL aircraft, this artist plotted its flight path to create a self-image the size of the The Projectplanet. The idea was conceived as a graduation project for Erik N.'s Advertising & Graphic Design major. It quickly became an Internet hit. Some irate people questioned the wisdom of wasting so much fuel on such an endeavor. Mr. N. no doubt has a corner office in a Madison Avenue high-rise by now... or at least a good job with DHL.

8-18-2008

RF Cafe: Science & Engineering TattoosLots of people are passionate enough about their life pursuits that they are willing to indelibly emblazon their flesh with monuments to those obsessions. This guy evidently loves tuned antenna circuits. Others love mathematics, causing them to have the Golden number documented to 80 significant places. It gets much weirder. BTW, I saw this bumper sticker from a tattoo shop, "Yes, It Hurts!"

11-17-2008

RF Cafe - Chip artBack when substrate real estate was not deemed as valuable as it is today, project managers tolerated IC layout engineers' proclivity for play. These examples of what has come to be known as "chip art" are the semi equivalent of software "Easter eggs." They are usually discovered as a result of decapping an IC for reverse engineering exercises. Pretty cool.

10-20-2008

RF Cafe Cool Pic: World's largest solar arrayThe Castile-La Mancha region of the Cuenca province in Spain will soon be capable of generating 18 MW. That is enough electricity to supply 9,200 households. Kyocera is supplying the photovoltaic modules. It will be one of the largest solar power generating facilities in the world. 89,320 PV modules, and 3,300 tonnes of structural steel were needed. The total site will have a surface area of 80 hectares and cover a space larger than 100 football fields. Quick Calc: At $4.75/W, the cost of the PV modules is about $85M (not including structures, control, distribution, etc.).

9-22-2008

RF Cafe: 1.5 MV Tesla coilThis 1.5 MV home brew Tesla coil is the handiwork of John Miles and his team, initially built for use in a Halloween spook house. The primary is 6 turns of #6 AWG solid copper; the secondary is 700 turns of #22 polythermalized magnet wire wound on a 20" diameter cardboard form at a spacing of 10 turns per inch. A 14.4 kV, 5 kW power-pole transformer fed power to its 10-pole, 3,000 rpm rotary spark gap.  Click here to buy a Tesla coil of your own, if you do not have time and/or resources to roll your own.

8-25-2008

RF Cafe Cool Pic: ElectraFlyer C Electric-Powered AirplaneThe electric propulsion evolution revolution is not the sole domain of ground-based vehicles. The ElectraFlyer C has pushed the e-frontier a little farther with its custom-designed super high efficiency, light-weight, 18 HP motor. It will not be performing unlimited vertical aerobatics anytime soon, but with 90 minutes per charge and zero emissions (and near silence with its low rpm prop), it will be a good motivator for follow-on efforts.

11-24-2008

RF Cafe: Scaled photo of 426,000 discarded cellphonesThis gray noise is actually a scaled photo of 426,000 discarded cellphones. That is the number of phones trashed every day in the U.S. alone, at least according to the artist that composed the montage. The original print is 150 cm x 275 cm.

10-27-2008

RF Cafe: Firefox Crop CircleEvidently, the most intelligent beings in the universe prefer to use Firefox when surfing the Internet. The story released for public consumption says that some Oregon State U. students made it by stomping down oats, but we all know it's another Area 51-type cover-up. Watch the video to see the method behind the madness - quite impressive.

9-29-2008

RF Cafe: GeoEye's Ikonos satellite view of ancient observatoriesWhen the Ancients weren't using them for digging hearts out of unwilling human sacrifice victims, they used these sophisticated temples for scientific astronomical study. Layout and orientation was very precise. Precession of the equinoxes causes them to be inaccurately configured for the current epoch. Here are views of the temples/observatories from the vantage point of GeoEye's Ikonos satellite, 423 miles above Earth at an average speed of 17,000 miles per hour.

9-1-2008

RF Cafe: Pike's Arithmetic text bookA copy of "Pike's Arithmetic," believed to be the first mathematics textbook in America, is due to be auctioned along with his personal journal with "notes, drawings and calculations on various subjects including mathematics, navigation, and astronomy, dated 1764," according to the auction brochure. Pike's Arithmetic was the dominant math text in the U.S. for 50 years. The collection should be worth about $20,000 to $50,000.

12-1-2008

RF Cafe Cool Pic: 80 meter antenna made from metal waste basketsBelieving that necessity is the mother of invention has caused amateur radio antenna designer ZL1CLG to use some very unusual on-hand components for his implementations. The one shown here is made of metal waste baskets for the 80m band. There is also one made from those grease splatter screens used for cooking and another from stove pipes.

11-3-2008

Sea-Based X-band RadarIt looks like an oil drilling platform, cruises like an oil drilling platform, and is semi-submersible like an oil drilling platform, but it's not an oil drilling platform. Boeing's Sea-Based X-Band Radar is a converted commercial oil drilling platform that is part of the Ground-Based Midcourse Defense system. Systems include X-Band Radar, In-Flight Interceptor Communications System Data Terminal, and the Ground-Based Midcourse Defense Communications Network. With a 6-kt cruise speed, you won't be skiing behind it.

10-6-2008

RF Cafe: College PranksSome colleges are famous for their curricula, some are famous for being party schools, while others, like these featured schools, are famous for the pranks pulled off by their engineering students. Of course, some are famous for all three - and more.

9-8-2008

Windfreak Technologies SynthHD PRO - RF Cafe
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TotalTemp Technologies (Thermal Platforms) - RF Cafe

Anatech Electronics RF Microwave Filters - RF Cafe