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Odd Lots


  1. Tom says:

    Jeff, I hope you are feeling better — you have been missed.

    Rate Gyros vs Directional Gyros. To the best of my knowledge the MEMS gyros that are used in hand held electronics (and RC helicopters) are Rate Gyros and not Directional Gyros as the article seems to assume. A Directional Gyro, which is what most people picture as a gyroscope is the kind build with the spinning wheel that tries to maintain a fixed direction in space if set in proper very low friction gimbals. The MEMS Gyros do not do this but provide an output signal proportional to the angular velocity about an axis.

    Since, with a digital computer, one can integrate the angular velocity signal accurately and cheaply you can CALCULATE the angular changes from an initial direction so you can get directional information from a RATE gyro and if you differentiate the angular direction signal from a position gyro you can get the angular rates. Today, the former appears to be easier, but it was not always so.

    If anyone is looking for what I think was the best description EVER of how Gyroscopes — of both types worked — try to find a copy of “Basics of Gyroscopes” by Carl Machover. I still have my treasured first edition from 1960 on my book shelf. It will also give you a deep appreciation of how engineers of that era made do with what we would consider almost impossible limitations of technology today.

  2. Actually, the NY Times bestseller list has been a running joke for years among authors. It never has had much to do with actual sales, but they lost me completely when they arbitrarily decided not to include J. K. Rowling’s books because her Harry Potter books were taking up slots that the NYT thought should be available for more worthy books.

    Also, they don’t really include ebooks, just those offered by some (by no means all) traditional publishers. They completely ignore indie authors, some of whom belong there. Amanda Hocking, for example, is a self-published author who’s now selling 15,000 books a *day*. (Granted, that’s total sales for nine titles, but IIRC her bestselling title is selling more than 40,000 copies a week.) She doesn’t count, as far as the NYT is concerned.

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