We had a fantastic time this weekend at the US Science and Engineering Festival in Washington DC. Among the highlights of our visit, we sat insanely close to the stage for the Q&A with Mythbusters Jamie Hyneman and Adam Savage. We also had the pleasure to meet fellow diy Science authors Theo Gray (Mad Science, The Elements, Popular Science’s Gray Matter, etc.) and William Gurstelle (Backyard Ballistics, Whoosh Boom Splat, The Practical Pyromaniac, etc.).
I urgently needed a high-intensity UV/IR/visible light source for a work-related industrial inspection project, so this weekend I recruited Abigail to help me build a 10W LED flashlight that features swappable UV/IR/visible heads. We decided to document the build since this flashlight would fit nicely in a photographer’s kit for light painting, IR illumination, UV reflected photography, or UV fluorescence photography.
Our flashlight is based on LedEngin’s LZ4-40____ series 10W LEDs. These are available in wavelengths ranging from the infrared through the ultraviolet. White-light LEDs of different color temperatures are also available as part of this series.
WARNING! This flashlight is capable of producing very powerful invisible radiation in the UV and IR. The eye’s protection reflexes do not work at these wavelengths, and may thus cause extensive damage if exposed to direct or specular illumination. In addition, UV at 365nm may cause damage to the skin. Never point this flashlight at anyone without taking proper precautions!
I purchased two “Giant Super Sensitive MC6” GM tubes from Electronic Goldmine (Item Number : G18717, Unit Price: $89.95). These are Russian-made new-old-stock model MC6. They are 10.25″ long x 0.9″ diameter. I compared the sensitivity of these tubes to the other GM tubes that I use with my CDV700 Pro Geiger Counter. I posted the results at:
I had some business meetings in England this week, and on my way back to Birmingham Airport I stopped in Stratford-Upon-Avon to see the houses where Shakespeare was born and died. Warwick Castle was also along the way, so I stopped briefly to take a few pictures before sunset. Continue reading
On a recent trip to Israel, Abigail (10) saw a very pretty, large, and expensive sand pendulum. In it, the pendulum was able to swing, while at the same time, the sand pan was able to rotate freely. We applied our motto “Why buy it if we can MAKE it!”.
Growing up in Ecuador, Maggi Sauce was always available at our table, and Maggi bouillon cubes were part of many of our cook’s recipes. On the odd Sunday that we didn’t have lunch out, my mom would prepare a Maggi soup (usually cream of mushroom or asparagus, being my father’s and my favorite), and there was always creamy onion dip prepared from an envelope of Maggi onion soup when we had guests. As such, Maggi soups do bring me fond memories, but I never thought someone would like them SO much as to go to a restaurant to eat freshly reconstituted soups and casseroles from a Maggi envelope… Continue reading
2 Weeks ago I visited one of our patients in Germany. The hospital was close to Leipzig, and I had a few hours to stroll through town. I went to the Museum in der Runde Ecke, which documents the power and banality of the former district headquarters of the East German State Security Service or “Stasi” in Leipzig, Germany. The exhibits are only labeled in German, but an excellent audioguide was available for 4 Euros. Continue reading
The high-gain antenna on my space communications array is based on a Fortec Star 120 cm dish. This is a high-quality, large dish designed for motorized FTA reception of analog, digital, and high-definition programs on Ku band satellites. I built a feed that combines a KU band horn for free-to-air (FTA) satellite reception with a helical feed for transmission and reception in the amateur L-band (23 cm, 1,296 MHz).
Being a peace-loving atheist, I am not interested in the religious and radicalized political junk that is most prominent over FTA. Instead, I use the Ku-band transmissions from geosynchronous FTA satellites as known-Az/El beacons to calibrate the aim of my array.