Putting up a vertical antenna part 4 – Antenna built, first measurements

20161015_114313This is the antenne in its provisional location.

 

 

 

 

 

What i have done is create three plexiglass spreader at the base of the antenna, at 2m60 and 5m20 from the base. Through the spreaders i guided 0.5mm copper wire i bought at the DIY shop and fixed the two wires at the base of the antenna.

 

The big moment. SWR measurements. I hooked up the antenna analyser and got the following result:

20161015_114557WOW! Not so good. What could be wrong? I checked the connections, nothing wrong there. I checked the radiators, all good. No, i am not using radials yet, but could this make such a big difference?

What if i switch the connections? Let’s just try it.

 

 

 

20161015_114756Now that looks a lot better! We have a dip around 40m, 20m, 12m (no 15m?) and 10m, so that’s a good start. I wonder if i wired the choke the wrong way? But why didn’t i see that when i put up the antenna last week? Hmmm, questions, questions, questions.

Next step is putting the antenna in its final location and build out the radials set.

To be continued.

Putting up a vertical antenna part 3 – The choke and first test

20161008_173239So this is the choke i built. Let’s see if it works against RF in the shack.

The XYL is not at home so i put the antenna up in a place where my cable reaches. It’s close to my house, but at least i can do my first run with the analyser.

Turns out i have a reasonable SWR on 40m and a close to perfect SWR on 12m. And this is without any radials. Here is the video of the first analysis (sorry for the bad focus, this is recorded on a phone with a huge scratch on the lens protection.

Worked European stations on 20, 40 and even 80m tonight.

Putting up a vertical antenna part 2 – The plan

img_20161008_145654So the plan is the following:

  • Two radiating elements will be added for 10 and 20m. The elements will have a length of appx. 2.60 and 5.20m. The exact length will be determined by my antenna analyser.
  • The main element will be adjusted to length for 15 and 40m. This -should- already be done, but because every situation is different i just want to check and re-check. Just in case.
  • 2 sets of 4 radials will be added for the 10, 15, 20 and 40m bands.
  • The antenna will be hooked up to a common mode choke built around a FT240-031 core according to the design from DG0SA.

20161008_144034

Bought some stuff this morning in the local DIY shop and first thing i’m going to build is the choke.