Chip Douglas @Diptchip@qoto.org

"be creative, computers can't be creative it's the one way to be sure you'll always be relevant"

> Thread of DALL-E AI generated images and their prompts https://twitter.com/BecomingCritter/status/1511808277490896903

welp that's it *packs up bag, packs up everyone's bags*

There has been a lot of discussion lately, much of it just plain incorrect, about the relationship between resonance and antenna efficiency. Many incorrectly claim that resonance has nothing to do with antenna efficiency at all, similarly others incorrectly claim that resonance is a direct indication of efficiency. Neither of these statements is true. The reality is that resonance does have a significant impact on how efficient your antenna is, but the relationship is highly non-linear and depends on many characteristics.

Below I have attached a chart hat plots out the total radiation resistance (R_r) vs the measured input resistance (R_in) of a dipole. Efficiency is just R_r/R_in. In other words an efficient antenna will have 100% of its resistance as radiation resistance, and R_in is **always** larger than R_r (since it is essentially ohmic resistance plus radiation resistance). When these two numbers differ significantly an antenna is inefficient. The source for the chart below is here and it gives much of the math if you want a deeper dive:

https://nptel.ac.in/content/storage2/courses/108101092/Week-2-Dipole%20Antenna.pdf

What is important to note here is that at anti-resonance we see a **huge** R_in value and a small R_r value, this means an anti-resonant antenna will have very high losses. Keep in mind the graph is very hard to read for the values <0.5 in length because the resolution isnt high. But there is significant divergence there as well. Notice at ~5/8ths wavelength antenna would exhibit very significant internal ohmic losses due to heat.

#hamradio #rf #radio #ee #electronics #electricalrngineering @Electronics

Big Tech is targeting you, and you're next!
https://yewtu.be/watch?v=A8lHsIf6aA8

There's really nothing to say about this. It's not like everyone hasn't been told to stop using it for 20 years already!

https://arstechnica.com/information-technology/2015/08/even-when-told-not-to-windows-10-just-cant-stop-talking-to-microsoft/

Bugs in billions of WiFi, Bluetooth chips allow password, data theft
https://www.bleepingcomputer.com/news/security/bugs-in-billions-of-wifi-bluetooth-chips-allow-password-data-theft/

Internet doesn't get any better than this: https://youtu.be/CAyWN9ba9J8

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Both squares are actually the same color here