Unique broadcast from WA2XMN on 42.8 MHz on the 19th of June 2025
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While we are all familiar with the 88 to 108 MHz FM broadcast band today,
its origins can be traced back to 1936 with the very first experimental
station...
1 hour ago
Here you go Bill.
ReplyDeletehttp://www.eso.org/public/videos/vlttrailer2009/
73s de WP4BQV/VQ9BQV
Anybody know what the laser was doing? Calibrating distance to a geo-stationary satalite?
ReplyDeleteThe laser is projecting a "virtual star" in our atmosphere, allowing the telescope to computationally subtract the "twinkle" caused by turbulent air from the other stars in the image.
ReplyDeleteHi Bill
ReplyDeleteIn 1992 I was invited to go to the factory that was polishing the mirrors for the VLT. It was a very interesting trip and the technology being used was fascinating. To prove out the process, they started by grinding a concrete blank. It was the smoothest piece of concrete you had every seen!
The mirrors are also ridiculously thin and would break if it wasn't for the adaptive supports behind them. Really great trip and a total surprise since I was really visiting a sister company.
73 Paul M1CNK