Copasetic Flow

While searching for low frequency, high current amplifiers I cam across the following two articles in an issue of Popular Science from 1944 on Google Books . The first is a great article on how oscillators work and what they are used for. The second article is on iron. The great part is that there's a "try it at home" recipe for thermite and a primer on the first page of the article. They definitely know how to grab and hold a reader's interest. Finally, check out the whole issue at the link above. There are lots of other cool things like two color pages containing Disney created fighter squadron insignia, (some of which are shown above). For the moment, the Google Boooks embed code below has gone loopy, so follow the links to the magazine articles. Oscillators: Thermite:

The following is from "Studies in the history of general relativity: based on the proceedings of the 2nd International Conference on the History of General Relativity, Luminy, France, 1988"

A while back, I reported that Agnew Hunter Bahnson Jr. was named after the pair of doctors that removed his grandfather's elbow. The elbow bone wound up in the possession of another grandson, Dr. Henry Theodore Bahnson M.D. I turns out that Dr. Bahnson was the first surgeon to successfully perform a heart and liver transplant. He studied under Alfred Blalock and in the Bahnson family tradition named his son Alfred Blalock Bahnson. Dr. Bahnson is shown with Dr. Blalock below, and, (I believe), Agnew. Dr. Blalock was featured in the movie about the life of Vivien Thomas , the African-American surgical technician who developed procedures for treating blue baby syndrome in the 1940s.

I'm attending SPESIF 2012 this week at the University of Maryland. I'm learning a few tricks for getting around the area easily since I'm using solely public transportation on this trip. Getting from the Airport to the University: The B30 metro bus leaves the airport every 40 minutes or so [pdf]. It costs $6 and you have to have exact change. It will take you directly to the Greenbelt Metro station. From there, you can ride one stop on the metro train to the College Park Metro station. University of Maryland College Park Shuttle System: From here on out, you can get a remarkable number of places on the UMD shuttle bus system. Make sure to check the complete schedule and maps [really big pdf[ to see if where you're headed is on a route. You can also use the excellent NextBus application on your phone. Just click on the NextBus logo in the upper right corner of the UMD transit web page . To get from the College Park Metro Station to campus, hop on the 1...

One of the Podkletnov rotation magnetic field arrangements essentially 'points' a set of solenoid at the side of the superconducting disc. I came across a demonstration from the 1963 movie by Alfred Leitner about liquid helium that uses a very similar setup. The superconducting disc in this case has been replaced by a diamagnetic copper cylinder.

I've come across another excellent amateur radio book from 1922 . The book details all manner of circuits and apparatus including the variometer shown to the left. The variometer was a couple inductance device that worked by rotating one 'honeycomb' coil within another. When the coils were at right angles, very little coupling resulted and when they shared a parallel winding axis, the greatest inductive coupling was obtained. The book also contains an inspiring discussion of the value of amateur radio to students. It's excerpted in the two pages below:

In his 1992 Physica C paper, Podkletnov references the use of a toroidal solenoid as the levitation coil for the superconducting disc. In Hathaway's 2003 reported replication attempt, he describes the same coils as pancake coils. It was unclear to me if a toroidal solenoid and a pancake coil were in fact the same device. It turns out that they are in fact different names for the same thing. See the page excerpted from the "Standard Tables and Equations in Radio-Telegraphy" by Bertram Hoyle, (1919), below. References: Podkletnov, Nieminen, Physica C, 203, (1992), 441 Hathaway, Cleveland, Bao, Physica C, 385, (2003), 488