• Matt Blaze@federate.socialOP
    3·
    6 days ago

    There were three AT&T radiotelephone sites in the continental US, each with its own transmit and receive antenna farms: Ocean Gate, NJ (shown here, serving the North Atlantic), Miami (serving the Caribbean and the Gulf), and Point Reyes, CA (serving the Pacific).

    All the sites have by now been razed, either for redevelopment or as nature preserves. The antennas (including this one) are mostly gone now.

    • Matt Blaze@federate.socialOP
      3·
      6 days ago

      Ships on the high seas still occasionally make some use of shortwave radio, but its importance has greatly diminished over the last few decades. The Coast Guard still maintains a “watch” on emergency shortwave frequencies, listening for distress calls, but most transoceanic ships are now equipped with more modern, higher-bandwidth satellite communications systems.

      Places like this are what the Internet looked like a century ago. Infrastructure is often heroic, and occasionally looks the part.

      • Passim@zirk.us
        3·
        6 days ago

        @mattblaze@federate.social It does look heroic! The golden age of wireless.

      • Matt Blaze@federate.socialOP
        3·
        6 days ago

        I should note that while the site (and its cousins) had a number of large discone antennas like this one, they were mostly there as backups in case the main antennas (which included truly massive wire rhombics oriented toward various oceanic regions) or transmitter combiners failed.

        The old Bell System did not mess around.

        • Luk@mamot.fr
          2·
          6 days ago

          @mattblaze@federate.social that’s very cool, thanks for sharing!

        • Matt Blaze@federate.socialOP
          2·
          6 days ago

          By the way, here’s what I believe was the final published frequency list and schedule for the AT&T high seas service, (a souvenir of one of my visits to the station before it went off the air).

          • Matt Blaze@federate.socialOP
            2·
            6 days ago

            You’ll notice that each site operated on multiple frequency pairs across the HF spectrum. This was for two reasons. First, each channel could only handle one call at a time, and so this allowed for more simultaneous traffic. Second, not all frequency bands were usable (due to atmospheric and geomagnetic conditions) at any given time. So in practice, at most half a dozen or so ships PER OCEAN could use the system at any moment.

            Multiple transmitters shared the antennas using tuned combiners.