Love this kind of tweaking!

Related and in the same manner is to make PCB antennas slightly longer than what you think you need, then tune by shortening (ie cut it with a knife) mm by mm and measure. When you get the desired freq response, this length is what you'd use in the next/final revision of the hw.

But that's probably only the most low-cost designs - I think most use a pi matching network: https://coil32.net/online-calculators/pi-matching-network-ca... since it gives more flexibility and can cope with more severe impedance mismatches.

(this is on sub-/2.4 GHz, don't know how it works for much lower or higher f)

I guess those are related to chicken bits, where you have some internal register in an ASIC which allows you to enable/disable a silicon feature in software before shipping.

https://en.wiktionary.org/wiki/chicken_bit

I have wondered what those dots are for, but never asked. Thanks for posting an informative article.

Interesting, this site doesn't even support TLS 1.1 and Firefox refuses to open it.

there was something special about the dots in the eye of the chickens, something about the distribution of dots in the brown or golden part of the eye, cornea?