This is a quick snapshot of my home made 20 meter quarter wave vertical that I made out of an old CB half wave Silver rod. It is just over 5 meters in length and has 3 radials each 5 meters long and coming down at around 45 degrees. It works quite well and I have had some good contacts around Europe and even a few stateside ! The aerial isn't very efficient but does have a very wide bandwidth and an S.W.R of 1:1.1 is achievable across a large portion of the 20 meter band.
However the vertical will be coming down because as you can see, to the right of the vertical is the center of my half size G5rv. This is mounted in a fully horizontal position. It is not very high either at only 5 meters above the ground but it is does work well and is a good standard to compare my other aerials too.
I will be constructing a 40 meter delta loop and hopefully this will tune up on 20 meters too so that I can compare against the results from the vertical.
The idea I have for the 40 meter delta loop is a large horizontal triangle positioned at gutter height ( 5 meters above ground level ) and secured to the fascia board on the house and a conifer tree at the bottom of the garden. This seems the simplest method as the 4:1 Balun or even 9:1 Balun that I will use to lower the impedance to a more manageable level can be securely attached to the house and fed with the shortest length of 50 ohm coax possible.
Your thoughts and comments on this configuration are more than welcome.
73's
James (M6JDB)
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