Simple shortwave wire antenna in a room - best method to string it up?

[A.Z.]

well, willing to use the simplest antenna, one may build an aperiodic one, just pick a lenght of coax, the longer and fatter, the better; short the center and braid at one end using a resistor with a value near the characteristic impedance of the coax (e.g. 50 Ohm), next place a coax connector to the other end, but wire it "reversed", that is; the coax braid to the center and the coax center conductor to the connector "gnd", lay out the wire as possible and give it a try possibly using a run of regularly wired coax to feed it (through a choke) and connect it to the receiver