Topband: 160m T-loaded vertical antenna

Jo,YC0LOW yc0low at gmail.com
Wed May 28 03:32:19 EDT 2008


Last weekend, I finished installing the T-loaded vertical antena using the 
18m Spiderbeam fiberglass pole. It has 3 wire spokes for top load, each at 
15 meter long. Also, 3 elevated radials at 1/4 wavelength long in the height 
of 3 meters each. The elevated radials are still bended here and there 
according to my limited land-lot area. The SWR 1,6:1 at 1825 kHz. The lowest 
1:1 is at 1800 kHz. I think I must pull out radials in straight-and-level 
form to obtain the SWR match and resonance (at 1825 kHz) and will see if the 
radial wires would need trimming.

I am using coax Andrew 7/8 inch about 21 meters in length as feeder line. My 
shack is in the first (not ground) floor. So, both (coax and radials are 
elevated). I am using home-made UNUN dual impedance (12.5 & 24 Ohms) a la 
W2FMI

This is my first time to build vertical antenna for TX on topband. Would be 
very grateful to hear any advises on what to do best to optimise the 
antenna. TIA. Also, I'd like to express my gratitude to Bjorn, SM0MDG, for 
his suggestions and guidance in making this antenna.

I hope I can continue to present YC-land on topband. 73 de Jo, YC0LOW




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