All Band Dipole

Here we go again. One of these days I will end up with a simple all band antenna system that works well enough, is easy to use, is effective, efficient, mechanically sound, and all those things we like to see in an antenna system. A setup soooooo goooood that I won’t be tempted to mess with it.

Yeah, I am not there yet. Lucky guess.

I do have a system up now that is unique, and works, but it does not work well enough to give up on trying something new.

Actually, all-band is guilding the lily somewhat. All I need it to cover is 80,75,40,and 30 meters. I could do it with traps but I want to cover ALL of the frequencies in those bands and I want to do it with SWRs of less than 1.5:1. Okay, I know SWR is not everything. Some antennas with high SWR are very good performers. True, but my radios don’t like high SWR so I need some way of tuning things so that SWR does not become a factor.

My Main rig includes an automatic antenna tuner, so the job should be easy. It would be if I was satisfied to endure the loss in coaxial cable that I would get with SWRs higher than 3:1 on the line from the tuner to the antenna. I don’t want to do that. I figure if am going to go to the trouble of matching feedline to radio so I get a maximum power output, the least I can do is show enough respect for that power by not wasting it as heat in the feedline.

Also, I don’t like baluns. I don’t like building them, using them, or worrying about possible losses in them. At the same time I would also like to keep my radiation pattern as balanced as possible.

When you put all those ‘wants’ together, they point to the use of open wire line, a balanced tuner, and a non resonant dipole.

I have come full circle. That is what I had five years ago, before I began experimenting with antennas. Back then I wanted to get rid of the antenna tuner. I guess I still could by using transmission line matching transformers but just my luck I would find a frequency that I would want to try and the transformers did not want to match. No, got to be adjustable from inside the shack AND cover all frequencies in all bands from 80 to 30 meters. Hmmm….wonder if I should include the 60 meter section as well? Why not!

Predictable radiation patterns are a good thing. An 88 foot dipole will provide predictable patterns for all the bands being considered. It will not be super efficient on 80 or 75 but I am not going to be interested in low band DXing anyway. The 88 footer should be fine for locals out to 300 miles or so. That 88 footer is 44 feet per side. That will work out fairly well. My center support is at 50 feet. My end supports are high enough so that the 44 foot horizontal distance will still be elevated at 35 feet. Not exactly flat-topped, but better than a full sized inverted vee on 80.

I will use what is left of all that surplus RG62 coax. 88 feet for the antenna and two lengths of 100 feet to make some ‘open wire line’. Use the sheet PVC to make insulators. Always wanted to try that. The old 450 ohm ladder line is pretty old and beat up and I don’t want to buy any more of that stuff. I just don’t want to spend the money when I already have the materials for an alternate solution.

So here is hoping that this is going to work out well.

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