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Re: OT: Tubes (was PM demodulation)

Started by Jerry Avins November 4, 2004
Randy Yates wrote:

> Steve Underwood <steveu@dis.org> writes: > >>[...] >>What's this about old tube technology? What do big FM transmitters use >>today? Only the exciter has changed since the time Jerry was talking >>about. > > > Do you doubt that a freshly-graduated BSEE of the day would > most likely know little-to-nothing about tubes? When I was > going to DeVry in 1976, I was in the last class that was > formally taught tubes - the next class was all transistor.
If you want to think about old technology, consider amplidynes and the magamps that drove them. Some were used in the servos that rotated battleship turrets in WW II. The transducers were selsyns. What scares me is that I know how to build that stuff. Crudely, at least. Jerry -- Those who bomb airplanes, restaurants, and abortion clinics have taught me to distrust those who believe that morality is is written in a book. &#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;