[TowerTalk] Collins vs Modified Lewallen Feed Method

[Mike]

Hello TowerTalkians,

Been following the discussion on the K8UR array.  The discussions involved
the use of a hybrid couple/Collins feed method.    

The plan for 80 meters is to install a phased array from a 125 foot tower
(with a 2 element shorty 40 meter and a TH7DX on top with all coax lines
and control wires inside the tower).  Researching the phase shifting
approach to use and found the Modified Lewallen method doesn't use a dummy
load hung from one of the hybrid coupler ports as in the Collins Method
(Antennas and Techniques for Low-Band DXing by John Devoldere, ON4UN).  

For my application, the phase switching point will be 60+ feet up the tower
which would mean putting up a large dummy load (1500 Watts RTTY is used) at
that point on the tower.  

So what's electrically wrong with using the Modified Lewallen instead of
the Collins method?

	73,
	Mike, K4GMH

  


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