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THE KK5ID 6 METER ROTATABLE DELTA LOOP
PROJECT
Construction Details The Delta Loop is bi-directional, with usable lobes off the ends and has been one of my favorite antennas. I have found that it will perform quite well in a fixed position. The 6 meter loop is small enough to erect a form around it and I have done this with 1/2" electrical pvc schedule 40 pipe with dowel inserted inside for extra strength. The caps and tees were put on without glue at first to get the size and shape I wanted and then it was dismantled one section at a time and glued with pvc glue. After it was put together, I inserted one self taping screw at each connection to make sure that it was solid. The design of the support came from a sleepless night vision. Is it funny looking? Sorta! Can it be improved on? Yes. Does it work? You bet! The antenna works best if the "crust" "A" side in the drawing above of the "pie slice shape" is up and the support accomplishes this. You are now able to put it in a rotor and rotate for bi-directional transmissions. Impress Your Neighbors The electrical characteristics of the Delta Loop can be found in any antenna book so I won’t dwell on that aspect. The formula for the wire is 1005 divided by frequency. Or 20' 5/8" at 50.1. over all length. Editors note: If you want to make the Delta Loop free standing a sturdy umbrella base would make a good base for the antenna on the ground. Just check out this link on Google images and adjust the support pipe as needed to fit the base. Now you have a 6 meter rotatable loop sitting on the ground that can be turned! The legs
then will be 6' 8 3/16". I used 75 ohm coax, (rg11), because of the close
match to the 90 to100 ohm feed point. 50 ohm line can be used which will
have an SWR of 1.8 to 2.0 to 1 at the transmitter. The easiest way to
match is with a tuner, however a matching transformer of 75 ohm cut at a
quarter wave length times the velocity factor (.66) can be used to lower
the SWR when using 50 ohm. To me it is a lot to do about nothing. Just cut
the wire, attach the coax, connect to a tuner and get after it. I
painted my support black but you could paint yours red white and blue.
This would surely impress your neighbors. Mine is only up above the roof
line, maybe 30 feet or so and has shown good results in working Es. Tropo
should be a piece of cake and as far as F2, time will tell. I use a 20
meter multi-band Delta for 40 and up and it works as good as my tri-bander
in the direction of the wire and I also am able to do quite well off the
sides of the wire especially Es at HF
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