So pretty sure OP Was using just base Nrf54840 Xiao and NOT the “Sense” version. so no IMU or PDM… Plenty O’ Room…
WARNING …
I can’t emphasize this enough, look VERY, VERY closely at that end of the board. There LIVES a LONE resistor, probably the smallest Known to man I’m betting it’s almost not visible to the Naked eyeball,
so close to the edge , it should be Illegal
Beware of it and the traces around it.
Yes, @ PJ_Glasso is correct…
@ cgwaltney it was the basic XIAO without the PCM chip. And the wire was added into the antenna “circuit” GND without removing the antenna chip itself and replacing it. On the basic XIAO the PCM footprint GND was the easiest/safest place to add the wire to affect the antenna circuit. But not a substitute for replacing the original antenna and the need to re-tune the antenna circuit via the FEED.
I guess whar i am asking is i thought the blue resistor looking thing is the antenna… are you saying some of the 6 pins adjacent to it are also antenna pins?
No, that’s part of the PDM circuit, but the GND pin of that circuit is common to the antenna chip’s GND side. And since the PDM is empty, it’s safer/easier to solder a wire there instead of the the chip’s side contact. This is by no means a replacement for the antenna chip, just augmenting the RF strength of the existing chip antenna.
If you want to have a larger impact, replace the antenna chip with a better circuit/setup. The wire I added gave a 10db increase in signal inside my home which allowed me to get a reliable connection in a farther room which I was not able to get before.
Hey what do you mean about re-tunning the antenna? If i were to completely replace the antenna, wouldn’t removing the blue antenna completely, and then solder the signal of the new antenna to the “feed” and the shielding to the ground be enough? Isn’t the 2.4ghz router style antenna already tuned?
i think the point being that you cannot use 2 antenna… so i would not expect that leaving the “resistor” antenna in circuit with an external antenna would work very well IMO… also all antennas can be tuned with an in circuit analizer to focus in on one frequency for efficiency…
I got 10db in my setup by adding “two” antennas. It was not a scientific outcome or design, just an ad hoc solution that worked for me in that situation. It is not the way to do it “properly”, if you want to replace the existing chip antenna with your own “proper” design.
PJ 
