There have been a number of questions regarding the issue of feed line loss and ladder line eventually gets discussed. So I am curious, how does one begin to estimate the loss in ladder line?
So, for the case of 2 bare wires "somehow" spaced an appropriate distance apart acting as a feedline with SWR=1.000, what loss could be expected? (Loss due to SWR was very well covered here: What is the actual loss in a feed line with high SWR? )
I would think that spacing the wires farther apart would increase the impedance, lowering the current and thus the loss/100m (at a cost, perhaps, of more complicated and lossy impedance transformers at each end which I am ignoring). I would think that adding an insulator would (1) lower the velocity factor --somewhat increasing the loss by somewhat increasing the number of wavelengths at a given frequency-- and (2) add some sort of additional loss mechanism in addition to that which could be attributed directly to the velocity factor.
Is there a way to quantify any of this?