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My Antenna


 Half Wave Vertical Antenna











Another yet of my antenna is a half wave Vertical antenna ( home made antenna ).
Dimension of this antenna is 1/2 wave ( 5.5 meters ), or a little bit lengthen on the top for best SWR tuning
I have been using this antenna for checking the propagation, for local contact, for portable station and also sometimes for dx'ing and it's about 100 dxcc and iota worked by this antenna with height about 8 meters above ground.
Many thanks to my radio friend Didin 91FAT105 for helping me to built this antenna in the past time.



 half wave Vertical antenna


Loading coil and mounting support


Loading coil is formed by pvc pipe dia 1 inch, and copper wire dia 1 - 1.2 mm, starting 1 1/2 turns from bottom to center tap and continue until 7 1/2 turns ending on the top.
bottom tap connected to antenna ground/bracket, center tap connected to antenna connector and end tap connected to antenna radial.


Loading coil inserted to the mounting support


This antenna only has three ground radials @60 cm in length 


All parts for 1/2 wave Vertical antenna
4 pcs of aluminium tubing @1.5 meters length, dia 1", 7/8", 6/8" and 5/8" total length will be 5.5 meters for antenna radial.
And for ground radial is not critical, with ground radial or without ground radial this antenna worked properly.
I used 3 ground radials with alumunium tubing dia 3/8", @60 cm in length.




Skypper Antenna


 3 elements Skypper Antenna


1 element Skypper /Dipole antenna







Coaxial balun 
Made by winding ten turns of coaxial line about ferrite core



Coaxial balun is placed in the plastic box



 Dipole for Skypper antenna with Coaxial Balun



Ferrite RF Choke coil
Choke coil is made by winding two turns of coaxial line about a ferrite core
Coil is about two - four inchs in diameter and is placed about a quarter wavelength down the line from the antenna terminals. This device prevent r-f energy at the antenna from passing down the outer surface of the coaxial line
Remember : all energy must remain inside the line