[TenTec] OT: Simple antenna software w/impedance

[Peter Klein]

With all the discussion of optimum antennas and transmatches, here's a 
much more simple but related question:

Can someone recommend a (preferably) free and reasonably simple program 
where I could do some "what-if-ing" with a horizontal loop?

Background:  I want to set up a decent multiband antenna.  I used to 
have a tree in which I could hang a nice 80m inverted vee at 60 feet.  
It worked well.  Then the tree tried to kill my house (fortunately, it 
missed).  So the tree is now gone.  I don't have anything higher than 
about 30 feet now.  It seems like the best antenna for me will be a 
horizontal loop fed with 450 or 300 ohm line.  Maximum circumference 
will be about 220-240 feet around my backyard.  Probably 30 feet high on 
one side and 10 feet high at the back fence.  Before I start buying 
wire, poles, etc., I want to model a loop at the various possible 
lengths/heights and get an idea of what the impedances, reactances and 
angles of radiation will be on the various ham bands.

I was fooling with 4Nec2, but found it too difficult to use--it seems to 
assume that you know everything about the minutiae of advanced, complex 
antenna design before you start.  And trying things out led to long 
slowdowns on my relatively recent PC.  I just want to be able to tell 
the program, "here are the lengths of the sides, the heights, the 
frequency, maybe the transmission line.  Now tell me the impedance, 
reactance, angles of radiation, losses are on 80m.  Now how about on 
40m, 30m, 20m, etc.?"

Thanks and 73,
--Peter, KD7MW