"Dave VanHorn" wrote in message
...

I dont think you are missing anything. The feed points of each of the
radiating elements need to be in phase if 'broadside pattern max' is
desired.

Do you intend to build an array, or just trying to understand them?


Both. I have some FSJ1-50 that I got for the purpose.

The docs that I've seen are all pretty consistent on how it should be put
together, but I just don't understand the workings of it.

IF the coax had a VF of 1.0, then it would make sense to me.

Dave

Have you looked at the collinear antenna on the web written by "Brian
Oblivious"? He cuts the coax into equal lengths 1/2 wave each. And that
1/2 wavelength accounts for the velocity of propagation inside the coax.
So, each length is somewhat shorter than the free space halfwave It shows
how he connected lengths of coax to make a collinear array. In my opinion,
that would be a waste of that good coax you have.

I once manufactured a vertical collinear antenna that had only one feed
point and the other collinear elements were passively connected when stacked
below the "fed dipole".

Sometimes it is convenient to mount vertical half wave dipoles around a
vertical supporting mast and have a "corporate feed harness" within the
mast. That works well.