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 cu

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-calculator.html 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)