I have a few comments upon a parallel wire up a tower leg being an RF
short... In general this is true, assuming a few caveats... That the wire
firmly contacts the tower at intervals not to exceed 5% (1/20th) of a
wavelength (this is 14 feet on 80M)... that it is of reasonable diameter
compared to the tower leg... I.e. #16 or bigger (preferably bigger)...
The reason here is that the galvanized tower and the wire have different
velocity factors... If they are only connected top and bottom, after about
.05 wave there will begin to be a significant phase (i.e. potential)
difference between the two differing conductors... Given that those phase
differences at the top of the tower will reflect back to the feed point you
may find the feed point to be quite reactive - and once tuned up on a given
frequency, to be touchy about frequency excursions...
Denny
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