Use a steel wire rather than copper.
a half wave end fed would be 64-65 feet for 7mhz and higher frequencies. 33 feet if you want 14mhz and above. if you are up high enough you might let it drape down. Need a 49:1 unun to connect it to coax.
If you can put one end on the roof and one hang down you can run a vertical dipole.
The amount of radiation that the uBITX puts out would not be enough to harm although there is enough voltage you wouldn't want to touch the antenna while transmitting. There is about 60v of rf on the wire as measured by my old oscilloscope.I imagine that the receive quality inside would be severely diminished due to noise.
Raduino bracket and Ham_Made_Keys