[Elecraft] Off topic feedline question

[Michael Blake]

My 80M antenna is a low, loaded dipole fed with balanced window line.  As the center impedance is  low the high impedance window line tries to invert the impedance to a much higher value.  The feedline is only 25' long and terminates in a 1:1 balun which is then connected to a remote autotuner via 24 inches of 9913F.

The question is:

Has anyone run any RF loss tests on the commonly available 12 gauge clear PVC insulated "speaker" wire.  The impedance would be quite low, probably in the 90 ohm range, and world certainly handle the applied power (500 watts) but I have not been able find any information regarding RF loss.

Michael Blake
k9jri at mac.com