How To Add External Antenna To Cell Phone

Seeing the booster thread, I got an idea

So I take some 0.03 inch hardline (very thin shit) and a cell phone that I have been thinking about augmenting so it has a SMA connector on it, so I can advisedly analyze output functioning and possibly add together , filters, protection, external output data tap, directional antenna, etc to information technology (plain not illegal amplifiers )

I don't know much about how the output amplifier of prison cell phones is designed, but can I simply find the last point in the PCB before the cellphones antenna and solder in the hardline using minimal exposure of the center conductor of the coax? Exercise I need an impedance matching circuit? Cutting the trace right afterward the output

I kind of don't fifty-fifty know where the antenna is. Is it one antenna?
Hither is a moving-picture show I found
https://d3nevzfk7ii3be.cloudfront.net/igi/kKUarywLm6AbxEkF.huge

The phone in question is a LG G4.

My plan was to but use a nearfield probe to meet where the signal is the greatest simply I figure I would ask before I potentially destroy alot of money.

Too, if I modded the chassis, would putting an RF relay or switch exist feasible?

I idea perhaps this is difficult if they utilise some kind of highly integrated rf SOC where you can't intercept the analog data earlier an amplifier.

I remember it has something to practice with that via stiched trace on the bottom of the picture, information technology looks similar the most RF affair there.

And I know the probability of success is low, only something interesting and complicated like a cell phone would help me learn this stuff better considering its interesting, and peradventure make me feel meliorate well-nigh spending money on the PLUTOSDR, I get irritated when I cannot at least go some fun out of my machines.