• Matt BlazeOP
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    221 days ago

    For much of the 20th century, the backbone of the AT&T “Long Lines” long distance telephone network consisted primarily of terrestrial microwave links (rather than copper or fiber cables). Towers with distinctive KS-15676 “horn” antennas could be seen on hilltops and atop switching center buildings across the US; they were simply part of the American landscape.

    Most of the relay towers were simple steel structures. This brutalist concrete platform in San Jose was, I believe, of a unique design.

    • Matt BlazeOP
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      321 days ago

      The San Jose Oak Hill Tower is unique in a number of ways. The concrete brutalist design appears not to have been replicated anywhere else; it seems to have been site-specific. It sits atop an underground switching center (that was partly used for a military contract), which explains the relatively hardened design.

      Today the underground switch is still there, owned by AT&T, but the tower space is leased to land mobile and cellular providers. The old horn antennas at top are disconnected.

      • Matt BlazeOP
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        321 days ago

        With a few exceptions (a few towers atop downtown switching offices in populated areas), no one was trying to make any of this utilitarian communications infrastructure beautiful. It was form strictly following function, built to be reliable and rugged.

        But there was, I think, quite a bit of beauty to find in it. I wonder if we’ll look at our current neighborhood cellular towers, now often regarded as a visual blight, the same way decades after they’re (inevitably) also gone.

        • Nate Vack 🍴
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          121 days ago

          @[email protected] It never ceases to amaze me how quickly we built and abandoned huge, wonder-of-the-world-scale infrastructure projects. We pulled twisted pairs of copper wire to the large majority of structures in the United States!

          And then almost entirely walked away from it

          look on my works, ye mighty, and despair

        • Farce Majeure
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          121 days ago

          @[email protected] any idea why they decided to do this strange design? Seems like a lot of overkill: it’s not in tornado alley, not in hurricane bowling land, and it doesn’t seem like reinforced concrete would be better for earthquakes than the traditional metal tower.

        • Bob Poortinga
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          120 days ago

          @[email protected] Aren’t microwave networks still used for High Frequency Trading? I know that these are not the same as the AT&T microwave network, rather they are relatively new facilities purpose built for HFT.

          • Matt BlazeOP
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            120 days ago

            @[email protected] Yes, high frequency trading is in a unique space- they don’t care much about bandwidth (compared with a telecom network), but they care a lot about latency. Microwave has a faster velocity factor than fiber, so a lot of the trading firms have their own microwave links. Generally shorter distances (a few hops at most), though I believe there’s a network of relays between Jersey City and Chicago (mostly using old AT&T sites with newer equipment).