Yeah this chart 543_Dallas shared is probably pretty much dead on for accuracy.
Made a Balun of RG393 4 to 5 turns of a 4 inch PVC drain pipe which is 4 1/2 inches in diameter, and worked great, as with no Balun is was just aluminum in the sky with no gain or rejection. We didn't have time or a longer length of coax at the time so we just made up something that we thought would work with a lot of black tape as it started to rain, and blow hard. The antenna was a 4 element Maco Beam converted to a hair pin match and separated driven element. Worked great even tho no skill was involved.
Jay in the Great Mojave Desert
Made a Balun of RG393 4 to 5 turns of a 4 inch PVC drain pipe which is 4 1/2 inches in diameter, and worked great, as with no Balun is was just aluminum in the sky with no gain or rejection. We didn't have time or a longer length of coax at the time so we just made up something that we thought would work with a lot of black tape as it started to rain, and blow hard. The antenna was a 4 element Maco Beam converted to a hair pin match and separated driven element. Worked great even tho no skill was involved.
Jay in the Great Mojave Desert
