... this is information relating to the 1950's microwave radio system for keeping the President, Pentagon and various hardened bunkers spread beyond Washington DC all yakking away during a nuclear attack. They all have code-names starting with 'C' for communication.
Microwave transmissions are 'line-of-sight'. Each receiver/ transmitter is on a high tower and can be seen by the next tower on the horizon. They are a more secure and highly capable means of sending information. As a child I remember occasionally seeing commercially operated microwave towers from the highway. They seemed impressive and ominous machines of doomsday.
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