[Elecraft] how did I calculate the loss?

[Stuart Rohre]

Don makes good points about balance.   Hams may over react to issues of
balance.
According to the noted antenna guru L. B. Cebik, he has calculated that even
in the extreme unbalanced case of the parallel line feeder end feeding a
half wave doublet, there is only about 10 per cent imbalance even with one
side of the feeder not connected to anything at the antenna end insulator,
and the other conductor connected to the end of the doublet.  That was an
eye opener.  Naturally, the capacitance from conductor to conductor and the
series inductance of the feeder must mitigate the extreme imbalance an open
circuit feeder appears to be.
73,
Stuart
K5KVH