I can’t comment on the transmission power and/or potential hack as I use the device solely to receive signal.
However, I can confirm that the above mentioned mod+ground plane antenna added significant reach (from 30ft indoors only to 250ft indoors/outdoors).
Would have to check regarding ground location but since the results are there not sure I’ll bother…
Hopefully someone can jump in to assist you regarding RF transmission power.
Cheers,