1996 - 2016
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...
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This collection of video and a few audio files represents files that have been featured on the RF Cafe homepage. Every week or so a new file is added that should be of interest to RF Cafe visitors.
Please send me an e-mail if you have a good subject. Note: "Videos for Engineers" formerly went by the name "Cool Videos."
MIT electrical engineering lecture, Professor Sussman explains how a mechanical watch mechanism relates
to an electrical oscillator circuit consisting of resistors, capacitors, and inductors. Sussman is a
life member of the American Watchmakers-Clockmakers Institute and exploits his expertise by demonstrating
via close-up camera how various parts of the watch function while explaining how they relate to electrical
components. This goes far beyond the comparatively lame textbook and classroom examples most of us have
experienced in college.
Officially, the U-2 is still the highest-flying airplane in the world. Its real max altitude is classified, but in this video James May of the BBC's Top Gear has the privilege of riding on the edge of space, at 70,000', where the Earth's roundness, and the thickness of the atmosphere separating terra firma from the black void of space is apparent. He comments how it is hard to not become emotional over the reality of seeing the home planet from such a vantage point.
Can you remember when the Rubik's Cube first came out? It must have been around 1980 or so, because I was in the USAF at the time. Don Hicks and I were the only two guys in our radar shop who took the challenge seriously, and I do not recall who solved it first. Neither of us got as good as this guy in the video, but we could whip through a cube in pretty good time. Eventually I bought one of the cubes with 16 squares on a side. Never did solve it.
I have to admit to never having heard of this band, OK Go. They and a cast of many created a pretty amazing, giant size Rube Goldberg machine.
One of my favorite parts is the bowling ball being launched across a fairly large distance and hitting its target to continue the machine's repertoire of imaginative gizmos. The video is nearly 4 minutes long.
Here is a video of some pretty spectacular lightning strikes on the world's tallest building - the Burj Khalifa Dubai. It was made on January 11th of this year. Handling 50,000 amps of current is no easy task, especially in an environment packed with sensitive electronics. I have not seen any reports of systems failing during intense storms, but that is no guarantee it has not happened. Uh-oh!
This is what might be considered the mechanical engineer's equivalent of an electrical engineer's cycles-per-second-to-Hertz converter. Come to think of it, though, there might be a huge market for this device under the new "green" energy policies. Maybe someone can package it commercially in the form of a light switch, calculate a carbon offset value, and collect millions in tax credits. Our Congress would be dumb enough to allow it.
A few years back, MIT began a program of publishing videos of many full courses, including
the electrical engineering curriculum. This particular video from course number 6.002 covers MOSFET
On-screen captioning follows popular Professor Anant Agarwal performance as he speed-writes/draws on the multi-layered electric chalkboard. A full transcript is provided for each lecture. It is a great way to brush up for an impending interview.
Intel has made a few pretty good videos in the last couple years. The best, IMHO, was the "Our rock stars aren't like your rock stars" commercial starring Ajay Bhat. This circa 2007 video, Wanted: Moore's Law for Another 40 Years, promotes their hafnium-based transistor breakthrough. Background music is Bobby Fuller's 1965 hit "I Fought the Law and the Law Won." This is very non-PC (guns used - a surprise coming out of the belly of the PC beast).
From the looks of this video, maybe the demolition experts should have budgeted for the extra sticks of dynamite or C4. One building fell to the ground whilst the second assumed the position of a popular tourist location in Pisa. Given the notoriety of the failure (including this mention), all the engineers on the crew are probably now helping to maintain track for the Beijing-Lhasa Express high speed rail system to Tibet.
Here is a case where getting two for the price of one is not a good deal. In July of 2006, a Chinook helicopter struck the 1000-foot transmission tower for television station WFXL, in Albany, GA. The tower had to come down because it posed a risk to the WALB tower standing next to it. Experts were called in. The WFXL guy wire charges went off as planned (visible in the video) and things were going well... until a wire from the collapsing antenna got tangled on the WALB tower guy wire. Well, that's one way to take care of the competition.
Watch a Nokia N95 smartphone drive this LEGO Speedcubing robot (big sport in the robotics nerd world). Constructed entirely from LEGO parts, it includes a vision system for ascertaining the cube's state while solving a 3x3x3 Rubik's cube from any start position in under 20 seconds, including the initial image capture. Thanks to a passionate, dedicated user base, LEGO has come a long way since introducing the blocks in 1949. They now carry a complete line of robotics devices, including processors, motors, and vision devices. Here is a nifty bit of trivia for you: LEGO is an combining of the two Danish words leg and godt, meaning play well.
Last October, students at the University of Southern Illinois launched a weather balloon laden with experiments and a video camera. Gusty winds made the inflation process a bit dicey, but the flight completed as planned. You can watch the balloon finally burst at 90,000 feet against the black background of space. The local electric company help retrieve the craft from a tree about 110 miles away.