You must have some stories to tell, well at least the unclassified ones. Can you recall what the original VHF frequency was? I believe it was just above 108.0 MHz. For the life of me I can't find the exact frequency anywhere on the internet.
The original system was built by Raytheon in 1961. All I ever found out said the original frequency was 108 MHz. I assume it was exactly 108.0 MHz but I never found out for sure.
They upgraded it several times and sometime in the 70s or 80s changed to 216.98 MHz with antenna mounted solid state amplifiers and power supplies.
Nothing about the system was classified that I know of. Field station employees did not need security clearances. Some of the people I worked with could never have even gotten one.
I don't have any interesting stories that have anyting to do with radio or electronics or the station itself. The 9 field stations were run by a contractor. It was a crappy low paying job. At the time I was there the contractor was an Indian tribal company. I was there 2 years and the Navy only showed up one time.
All we did at the transmit sites was keep a carrier on the air. We maintained the poorly designed equipment that probably worked fine in Raytheon's lab in Mass. but not outdoors in the heat in the southern states.
The receive sites listened for reflected echoes and measured the doppler shift and phase angle of the echoes and fed the data to HQ at the Space Operations Center at the Naval Surface Warfare Center in Dahlgren, VA. Maybe some of the data was classified after that but the field stations had nothing to do with it. I never visited Dahlgren or any other field stations so I don't know what the rest of the system was like.
Whoever wrote the
Wikipedia article got the frequency wrong and other information. It says 216.983 MHz but in real life it was 216.98. The fill-in transmitters in AZ and AL were 216.97 and 216.99. The signal was generated by HP 5061A cesium beam frequency standards. Some clown probably drove by with a cheap uncalibrated amateur/CB frequency counter that picked up 216.983 or something. Also the picture says it is from 2001 but it's a picture of the old wire ground plane that was replaced with aluminum panels in the 80s.