** UPDATE ** The laser is gone, tadalafil sorry!
I have been cleaning and found the need to get rid of a few things that I will never use. A couple of things that I would like to get rid of are a Melles Griot helium-neon 632.8nm 5mw laser. The laser is 5mW, on the order of a red laser pointer, but has a much better quality factor and is pretty good for laboratory use. It is free to the first person who claims it by email or comment AND pays for shipping. I am in the USA zip code 16802, the package will be 1.5 LBS at most and the size will be a little smaller than a shoebox.
Some time ago, I posted the schematics of Xilinx compatible parallel port to JTAG cables. Since then, I found more schematics that describe a complete Spartan-3 (or 3E) board including the same programming cable. These schematics include an FPGA (which can be as small as 100TQFP) and an SRAM chip with the intent of re-programming the setup at every powerup using JTAG. This can be extended by looking at page 67 of the V3.4 Spartan-3 datasheet. There are several methods of adding a configuration ROM to the device to ensure independent operation on power-up. Finally, the Xilinx ISE WebPACK can be downloaded to create basic bitmaps and actually send the code across providing a fairly limited, but free, development platform. Unfortunately, the Lattice Semi’s parallel port to JTAG cable is highly guarded proprietary information, so the same type of almost-free development solution is some ways off.
( livedesign_eb_schematics-xilinx_spartan.pdf )
As I am preparing for exams, for sale I am appreceating access to excellent books more and more. As a result, salve I have created a second site aimed at listing technical books that people find to be most helpful. It is my assumption that everyone has at least one favorite book on a technical/scientific subject whose title they could share with the rest of the world. If the site takes off, I will try to get a sponsorship deal with an on-line book retailer (amazon/bn) and use 100% of the proceeds to get the contributers gift/discount cards so they could in turn get more excellent books. If you have some books that you think are worth-while, please take some time to register and write a short post about them.
I just noticed that Tektronix has a special section on their website that is dedicated to aiding teachers with classroom and lab resources. They have some documents that are aimed at teaching people how to use their scopes, ailment whose contents can easily be applied generically to scopes from other vendors. They even have (a first in a series) pamphlets that are aimed to give a basic overview of some electrical engineering terminology. Although they are trying to sell their products, cheap the information contained is pretty universal. (Picture is from UMD.)
( 3gw_17276_0.pdf )
In exactly two weeks, sovaldi sale I will be taking the written portion of my graduate school qualifier exams. The first day will focus on applied math and the second day will focus on electromagnetic theory. The next few weeks will be focused on solving problems and polishing my knowledge of the theory, decease so some of the posts may be more theoretical in nature. Another consequence of this preparation is that I will be very justified to take a break from studying to answer any questions that readers may have in the fields of applied engineering mathematics of electromagnetic theory, so feel free to email them or post them in comments. The time frame for this is until the completion of the oral part of my qualifiers on 12th April, at which point my brain will probably explode.
“If I have seen farther, it is by standing on the shoulders of giants.”
- Newton, 1676
Nikola Tesla was undoubtedly one of the greatest inventors of the late 19th/early 20th century and a true master of the magnetic field. Although Tesla’s 150 patents pale in comparison to Edison’s 1000, it was Tesla that suggested an alternating-current power distribution system and is credited by some as the proper inventor of “radio” communication instead of Marconi. One might think that a man of such scientific merit would have a single devotion, however, Tesla was also a poet, a connoisseur of food and wine and an excellent swordsman. As a side note, it is pretentious to cite Maxwell’s treatise on electricity and magnetism whenever electrostatics are mentioned. However, in the spirit of one-up-manship, Tesla’s patents on electrical distribution can be cited whenever 60/50Hz noise is mentioned in a paper.
( 1916_my_inventions.pdf ) ( talking-with-the-planets-1901.pdf )
( pat0416194.pdf ) ( pat0455068.pdf ) ( pat0455069.pdf )
( pat0685958.pdf ) ( pat0725605.pdf ) ( pat0390413.pdf )
( pat1061206.pdf <- Tesla turbine)