[HCARC] Loop Questions

[Gary J - N5BAA]

Lew, Frank, Dale and Gale,

Why is it that when using 450 ohm ladder line to feed a loop to the radio are we are using a 4:1 balun instead of a 9:1 balun??  

BTW, what type of ladder line is best??  I have seen copper clad steel at 400 ohms and pure copper from Davis at 450 ohms with the all copper being cheaper than the copper clad steel – go figure.

For Dale, Gale and anyone else who does modeling:  Can you model Loops at approx 50-60 feet above ground??  It would be nice to know the best loop length for resonant points in the 160/80/40/20/15 bands for use at Field Day.  I.e. what length gives us the best choice of resonant frequencies.  The loop skywire website (http://n1su.com/loop.html) gives the following:

  a.. 565' is comfortably resonant at 1.778kHz, 3.557kHz, 7.115kHz, 14.230kHz and 28.460kHz.  
  b.. 574' is comfortably resonant at 1.750kHz, 3.5kHz, 7.00kHz, 14.000kHz and 28.000kHz
Is there a longer length that might even do better??  What might 1130 feet look like??  As you can tell – I don’t know squat about loops.

Gary J
N5BAA