Nationwide
The Nationwide or "Echo-Foxtrot" system was an Air Force One half-duplex single channel FM voice communications network that included about 100 sites located on AT&T microwave relay towers throughout the US, tied by leased voice channels to manual switchboard at White House ("Crown Control"). The network used 415.700 MHZ downlink and 407.85 MHZ uplink to Air Force One at rather low EIRP's (less than a few watts).
Sources and Resources
http://www.fas.org/nuke/guide/usa/c3i/nationwide.htm
Maintained by Webmaster
Updated Saturday, May 23, 1998 7:12:00 AM