Sunday, September 27, 2020

Fall Antenna Work

 Did a few Antenna projects spring and summer.  

 First was the 6m vertical with 8 radial placed at the top of the hill on the ground.    It really didn't work all that well compared to the 160m inverted L which loads perfectly on the low end of 6.  Next up was a 6m dipole at the top of the hill.  It loaded right up ,  1:1 VSWR and worked well sometimes better then the  160m inverted L.    Next up was a 6 wavelength end fed 6m long wire pointed more or less south.   It worked sort of but as it turned out I had a bad chuck of IFL.  Found that out when suddenly the perfect dipole no longer loaded!     

Ripped down the 6m long wire a few weeks after putting it up its not all that practical! 

Tore down my 15/10/6 m fan dipole next to the house.   The antenna was fed with around 200' of RG6 and worked fairly well.   It was only up for a couple of years and seemed to not be as good as install.  When I took it down I found that a critter chewed through the Coax ... was surprised it worked at all!  

  Decommissioned the faulty chunk of IFL and revamped another chunk,  the original direct cable that went the 500' to the top.   About 150' from the top the original  IFL is joined.  It was well taped but somehow when I took it apart there was water in the female N-N barrel.  Blew it out ,  sprayed with contact cleaner the add two new chunks of LDF4 once again taking me to the tp of the will.     Luckly it worked and this direct run is feeding my new Fan dipole.  


Built an 80/40/20 Fan Dipole ,  its at the top of the hill it runs N NW to S SE roughly broadside to the EU and Calif and the South Pacific.  The dimensions and design were in the previous blog post.   Put it up and I really don't need to do any tuning...


80m 

Freq      VSWR 

3.7         3:1

3.75       1.5:1

3.8         1:1

3.85       1.5:1

3.9         2.5:1     


40m

Freq     VSWR

7.0        1.2:1

7.05      1.2:1

7.1        1.5:1

7.15      1.6:1

7.2        1.9:1


20m

Freq      VSWR

14.0        2.2:1

14.05      1.7:1

14.1        1.2:1

14.15      1.2:1

14.2        1.6:1


Did a bunch of cable sweeping with the Nano VNA learned a ton but thats the next blog post.   Have started to think in terms of return loss vs VSWR.  It paints a much better picture of how things are performing.   




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