Topband: In search of resonance

[Tom W8JI]

Tom

<<Maybe you saw my post where I stated that the MFJ plunged to a minimum 
reading of 4 0hms at 1825?  Does this reading mean that the L is near ground 
potential and 'in union' with the grounded Skyneedle at that freq?>>

It could be from a few things, but two closely spaced conductors, with the 
"parasitic" conductor resonant near the target band of the fed conductor, 
commonly behaves this way. You might never be able to get Inverted L "real 
part" (resistance part) high at that spacing and length.

<<If I can't get the antenna to resonate using the L I'd say that I'd 
consider shunt feeding the tower and work out an (omega) matching scheme to 
match the tower to my target freq.  If that's the case, do I mount my upper 
shunt arm on the tower at 67' or at 90'? >>

There is probably some ideal point where the shunt capacitance is minimized, 
and that would be best. There are hundreds of points that will work, but 
they will have higher Q.

<<Can I run a single drop wire into my panel and then switch the feed 
between two matching networks?  One for 160 and one for 80?>>

I don't know. I've never looked at doing that.

73 Tom