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The article is not that good, but whatever. I am new to electronics myself and quite fascinated how has the art progressed in the past hundred or so years. The

• bowsamic 3y ago
  Electronics has and likely always will feel like arcane magic to me
  • al2o3cr 3y ago
    My favorite bit of "electronics magic": https://www.youtube.com/watch?v=PD7DzTIFJdU https://www.youtube.com/watch?v=PD7DzTIFJdU (this has more to do with TFA and impedance-in-general than might meet the eye at first glance)
  • BenFranklin100 3y ago
    Get this book: https://www.opencircuitsbook.com/ https://www.opencircuitsbook.com/ It’s a book featuring macro photographs of cut-aways of electronic components. It’s the first book that helped me really think of electronic components as a physical things whose function followed from physical principles, rather than an arcane collection of various bits of black magic strung together.
    • CliffStoll 3y ago
      Windell Oskay & Eric Schlaepfer's book has brilliant photographs and insightful text ... a coffee table book to delight any techie. They slice through connectors, semiconductors, and components ... showing the wonderful microscopic world of everyday electronics. A real joy!
    • NikolaNovak 3y ago
      I agree! I kinda know nothing about electronics since "my first electronic kit" as a 8 year old, and that book of cutaways shocked me as how many things in my computer aren't nanoscale magic!
  • nomel 3y ago
    It’s a beautiful demonstration of how increasing one parameter (frequency) can successively invalidate whatever model you’re using for the system, where negligible errors in the model eventually become functional circuit components.
    • detourdog 3y ago
      frequency exposes the efficiency of transmission through a material.
  • akiselev 3y ago
    That's why one of the best books on high speed digital electronics is titled High Speed Digital Design: A Handbook of Black Magic [1] [1] https://www.amazon.com/High-Speed-Digital-Design-Handbook/dp/0133957241 https://www.amazon.com/High-Speed-Digital-Design-Handbook/dp...
  • timemct 3y ago
    Especially when you think about what electronics are made of: things mined from the earth. They made rocks compute for us!
    • charcircuit 3y ago
      Where else would they come from, the moon? It's to be expected that for large scale products like computers to be made from common materials.
      • deleted 3y ago
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  • pclmulqdq 3y ago
    High-speed digital and RF are more "magical" than a lot of other forms of electronics. It is quite a bit more approachable if you limit yourself to ~200 MHz signals at most, then you don't really have to worry about the RF properties of your circuits as long as you keep the wires pretty short.
    • deleted 3y ago
      [deleted]
• kurthr 3y ago
  I like Rick. At least they got that it was the original coax cables that drove it. Then once you have lots of measurement equipment and cables, it's hard to change (even SMA is 50ohm). You can still get 75ohm BNC cables (close to 77) and 93ohms (and I think some 150/300ohm antenna cables?). Once you get over a few GHz all the inputs are balanced differential anyway and you have T networks to optimize power reflection. It doesn't mention at all that free space impedance that matters a lot to actual aerial antenna design is 377ohms. I don't know enough about it, but assume they're using transformers to balance loads (about 300ohms?).
  • Johnythree 3y ago
    The impedance of a folded dipole is 300 Ohms. And the impedance of a 1/2 wave dipole is 73.1 Ohms. However there are many other types of antennas see https://en.wikipedia.org/wiki/Dipole_antenna https://en.wikipedia.org/wiki/Dipole_antenna
  • pclmulqdq 3y ago
    Many antennas are designed for a given gain and polarization, and you get the impedance you get from the materials and geometry used. Almost all of them have a matching network at the entrance to the antenna, and usually one set up based on actual S-parameter measurements. If you're really fancy, you can get custom coax cables made to match your antenna at any arbitrary impedance, and then put a much better matching circuit in your rack instead of using one on the antenna. High-speed digital signals haven't entirely settled on 50 ohm (100 ohm differential) impedance, though. SSTL, HSTL, and POD (used by different types of memory and high-speed DACs/ADCs) often use 35-40 ohm impedance instead of 50. It's also not uncommon to see drivers having lower impedance and receivers having higher impedance (eg having a 32 ohm driver and a 48 ohm receiver on a 40 ohm wire) because a little bit of reflection can actually help signal integrity here. Long digital wires like twinax Ethernet are all 100 ohm differential signals, though, since reflection is not beneficial there at all.
    • kurthr 3y ago
      All the medium speed stuff I see (not 64Gb Serdes or even Thunderbolt) is differential current drive/receive though they may be voltage limited on the output. Those still seem to be designed as 50ohm, but they have some fairly high resistance connection's. Even at 1Gb getting a clean eye requires lots of equalization and careful routing, if you want to go 10+ inches.
• pid-1 3y ago
  > quite fascinated how has the art progressed in the past hundred or so years. There are people remembering "we were doing it wrong". Incredible If you think about it, that's practically a given in any engineering field that stuffers from high iteration / experimentation cost.