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Re: Helix feed

n6paa wrote:

>Just so I get this right the first time, I've wound a helix and I'm 
>ready to solder it to a Type N feedthru.  Which end do I solder. 
>This will be for RHCP to receive AO40. From the solder end, should 
>the helix winding be clockwise toward the dish? Thanks, ron n6paa

Quoting from a G3RUH article (ftp.amsat.org/amsat/articles/g3ruh/a116.zip) :

This is 3.3 mm diameter copper wire.  In fact it's the solid inner stripped
out of a length of H100 coax (similar to Belden 9913).  You need about 1/2
metre.  Wind it all, about four turns, around a 40mm diameter former.  I
found a socket in my car tool kit that was perfect.  It will spring out
slightly after winding.  Wind it left handed, that is to say in the
opposite sense to a conventional screw thread.  As you look at it from one
end, it will recede anti-clockwise.

It doesn't matter which "end" of the helix you solder, as long as 
it's wound in the direction described above.


Bill Howell
University of Texas at Austin
College of Fine Arts
Office of Computing Technologies
N5ALO  Amsat 32459  QRP-L 415
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