Radar Audio Feed--how do we do it?
It's simple. The Air Force Space Surveillance Radar transmits a
216.98 MHz signal into the heavens 24 hours a day, 7 days a week.
Meteors, satellites and spacecraft passing overhead reflect those
signals back down to Earth. The radar's primary antenna is located
near Lake Kickapoo, Texas. A few hundred miles away in Roswell,
New Mexico, radio engineer and long-time spaceweather.com associate
Stan Nelson picks up the echos using a yagi antenna on his roof:
these details: "I'm currently tuned to 216.97927 MHz. using
(USB) Upper Side Band on a ICOM R8500 receiver. The antenna is a
13 element yagi pointing east with a 15 degrees upward tilt. The
receiver audio is sent to a ACER PC (Vista Windows) line input.
The audio is encoded running Edcast using AAC at 16Kb. I have a
20 db. pre-amp at the antenna feeding about 50 ft of RG8."
Other ham radio
operators in the southern USA may wish to try picking up the signals
themselves. Sample reflections and observing tips may be found at
these web sites:
of Fireballs Past (Science@NASA)
about the radar: Formerly known as NAVSPASUR, the Air Force
Space Surveillance Radar transmits 800 kW of continuous-wave (CW)
radio power into an east-west oriented fan beam at 216.98 MHz. The
radar's primary mission is to track satellites and space debris
for the US Space Command. It can detect objects as small as 10 cm
orbiting 15,000 km above the earth's surface.
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