Wireless Joint

So, a long time ago, even some early smartphones had external antenna ports. At some point (around the time batteries became non-removable I think) they did away with this entirely. That being said, I *believe* these devices may still have ports for testing before final assembly and deployment.

Anyone know if they still work? Or would you likely be walled off by firmware?

I've done a moderate amount of work/disassembly on modern smartphones, and the temptation to get a new device for such a purpose is high... but also a risk for cost of course. Just considering it.

I've seen standard mhf4 antenna connectors inside the phones, but I havent seen extra "test" ports.

My wording may not have been appropriate, but yes, basically ports that could be used if the phone were to be diassembled. Maybe I should watch some videos of disassembly on some newer devices. Might be worth considering a S10 or something to use as a modem, get one with a cracked screen or something, hook up external antennas and usb tether it.

Not a bad idea. User BillA on here is a phone guy. He might know

I do believe they have test ports. The trick is that some have very tight specs on what or how often you can insert without breaking some fine spring inside. So I'd research the connector carefully... At some point a careful solder job may be better long term.
Something to consider is that I'd expect many phones to have multiple antennas and it may not be easy to figure out which is for what, between cell, wifi, bt plus mimo.