Anyone got information about the transcontinental land routes?
I was trying recently to learn when the first fiber optics made it coast-to-coast across the US (beginning to make the Long Lines microwave relay network obsolete), and I found it really hard to dig up anything at all. I know when the technologies were developed and commercialized, but had to make some educated guesses about the progress of their deployment.
> At least once in every five minutes the cable was used as a condenser. A charge from a battery of about one hundred cells was given and in turn discharged through a properly shunted Sullivan galvanometer and the “throw” of the needle carefully noted.
Note that “condenser” means “capacitor”.
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Another good read is the biography of Oliver Heaviside who is famed for his (armchair) contributions to both wireless and subsea communications!
For an exciting and gripping story of the laying of the first Trans-Atlantic cable check out A Thread Across the Ocean, by John Steele Gordon. It is quite the page turner.
Most people reading this will assume that the entire world has long since become accessible by radio. Not so. Actually, the ignorance has multiple layers:
* Part of the general public: "Cell phones work anywhere in the world". I've seen this even on Hacker News, during discussions of Apple's emergency satellite texting service.
* Another part of the public: "Cell phones have dropouts, but a radio can reach anywhere". Many signals can't cross the horizon, and those that can (MW and SW) can be very difficult to tune into.
* The most savvy among the general public: "The military must have radios that work anywhere". The military has various ways to communicate around the globe, but it's very expensive, bulky, or both; think Air Force One, a large network of ground relay stations and geosynchronous satellites, etc. Even a few miles can be difficult; in Iraq and Afghanistan, US forces outsie the wire had no assurance of being always able to talk to the FOB. This is just voice and perhaps low-bandwidth data, mind you. Yes, it is possible for a drone pilot in Nevada to control a vehicle in the Middle East, but the films that show high-quality real-time video from a drone being transmitted to a Pentagon conference room from which decisionmakers can make instantaneous decisions on what to hit are fiction.
This is why the military has bought into Starlink/Starshield so quickly. Suddenly, the status quo has moved from the above to voice, video, and broadband being available anywhere on the planet, whether air, sea, or land, possibly excepting a dense forest. While sailors appreciate having off-duty Starlink being rolled out aboard ship (so much so that sometimes they illicitly jump the gun, as we recently learned), the real breakthrough is in every single patrol in Indian country, FOB, base, ship, and aircraft being able to always talk to each other via a dish the size of a medium pizza. That it has been extensively combat tested in Ukraine is a bonus; the Ukrainian officials who said that without Musk's emergency delivery of Starlink dishes early on in the war Russia would have quickly won were not joking. I am told that now every single company, school, factory, building, in Ukraine has a dish.
> It's interesting - with such large defense funding, why did it take Starlink, a private company, to establish this network of satellites?
SpaceX has simultaneous pioneered vastly lowered launch cost by reusing rockets, and very sophisticated phased-array broadcasting technology that lets a small dish talk to thousands of satellites moving rapidly across the sky in low earth orbit without constantly moving around. SpaceX is still the only entity on earth reusing orbital rockets a decade after first doing so, and without that ability no one else—not even the US military—can afford to launch thousands of satellites and constantly replenish them because they only stay up for 3-5 years.
I was trying recently to learn when the first fiber optics made it coast-to-coast across the US (beginning to make the Long Lines microwave relay network obsolete), and I found it really hard to dig up anything at all. I know when the technologies were developed and commercialized, but had to make some educated guesses about the progress of their deployment.