4 Comments
Feb 29Liked by Liberty

Re fiber optics and only needing to upgrade the equipment at each end, for long point to point links like undersea cables the 'repeaters' tend to be Erbium Doped Fiber Amplifiers that don't actually repeat the signal by going light to electrical and back to light but instead amplify it directly in the optical domain without needing to know how the original signal was modulated, even by future ultrafast technology or future higher density wavelength division multiplexing to upgrade the link bandwidth. A relatively high power, high reliability pump laser operating at about 980 nm wavelength, excites the electrons in erbium which has been added to the glass in a loop of fiber in the amplifier, allowing spontaneous emission to optically amplify the lower energy (longer wavelength) photons that arrive in the 1550 nm wavelength band. It can even work bidirectionally for signals passing both ways along the same fiber and can sometimes include dispersion compensators to correct for temporal spreading of signals of different 'colors' within the 1550nm band over thousands of kilometres, though this could also be corrected on dry land at the end of the cable. The electrical power needed to run the 980nm pump lasers is why so much copper is needed in sub sea fiber optic cables.

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Very cool, thanks for the extra detail, amazing what we humans can come up with.

I was recently reading about the invention of fiber optics and how for a while they knew about it, but thought it was impossible to get clear enough glass for it to work over long distances (Bell Labs was looking at it in the 60s I think). Then Corning had proof of concept and went from there.

Thanks for reading, and writing, Ryan 💚 🥃

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Feb 28Liked by Liberty

Probably Apple could come up with a car human interface that was better than Teslas, and maybe get FoxConn to build a factory to build EVs, but a non-autonomous EV doesn’t have a big enough margin (see Tesla price cuts and Ford, GM and Volkswagen troubles ) to make it worth the big capital expense. Cruise has a big troubles, Waymo isn’t improving as fast as predicted and laws are still in the way, so even autonomous cars are ahead of their time, and Apple would be catching up. Working on a good device based AI would be great, especially since they already control their own processors. I would also love to see them improve the comfort and battery life of the Vision Pro, it’s great for 3D movies, but not 3 hour ones. It’s funny the called the car developers Special Projects Group, before I left Apple over 30 years ago, I worked in the Special Projects Group that then was working on replacing the Motorola CPUs in Macs with RISC processors, but we actually shipped some products. Before the SPG I worked in ATG, the Advanced Technology Group which was more advanced, but less specialized, and we worked on lots of cool, but unshipped products.

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Wow, very cool! I'm a big Apple nerd and have been reading a lot about their history, been listening to ATP and John Gruber for a decade+, etc. Small world that you were in there!

Agreed on cars. Way it would make most sense is if they could someone be a bit like Porsche, fairly low volume (but not supercar) and high margin, highly differentiated, etc. Much harder to compete with Model 3 level at high volumes with Apple-like margins.

But then, that product may not be worth the trouble of making for Apple's current scale...

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