Cette page était sur le site de SP3FHI; mais le lien ayant disparu, j'ai reproduit ici l'article que j'avais conservé. (F5AD)
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SP3FHI * POLISH AMATEUR RADIO STATION * SP3FHI
(SIERRA PAPA THREE FOXTROTT HOTEL INDIA)

MY 6M HEXBEAM ANTENNA

This hexbeam antenna is made of some easy to find and extremely cheap parts ($10 total).

I have started with drilling holes. Than attached bamboo sticks and painted them to protect against water. 

 

Than... I spent 5 hours trying to make a good hex shape! Why? Here is the conclusion:
- I have used too heavy wire (2,5mm2) and the bamboo sticks are too weak to give enough force ,
- to make it perfect first get the hexagonal shape of the external wires and then attach the radials the way not to loosen the external wires!
- the photo below shows another mistake; I've used some thin rope first and attached wires to it...wrong!...I've removed all the rope parts where the wire can hold the construction 

The dimensions taken from EI7BA site (driven 520/f and reflector 4% longer) are too long. Maybe there is a problem with my conversion - i convert to metric with a formula 1ft=0.305m. So using MFJ's analyzer i cut a few centimeters of both driven and reflector wires to get resonance on 50,200MHz. Than I had to reconfigure the wires to make the reflector cover the whole available space beetween spreaders.

SWR is not bad: in my garden keeping it 1m over my head i get 1:1,1. On the roof this antenna is mounted on alu 3m pipe with a TV rotor and there is a "pounder " antenna 1 m below.  The following results were measured using MFJ antenna analyzer with antenna on the roof.


 

Frequency MHz SWR
50,0 1,5
50,2 1,4
50,5 1,3
50,8 1,3
51,0 1,4
51,4 1,5
51,6 1,6
51,8 1,7
52,0 1,8


The next construction will be made of fiberglass and I will try a little diffrent dimensions and use some thin 1mm2 wire to get perfect hex and flat shape..

VY 73 ES MANY DX!
 
 

 

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