Actually it is quite simple: just take a random length of wire (the longer the better, depending on the lowest frequency), add a 1:9 balun and you’re done. Right? Right. Or wrong, when you’re living in a rural area.
I want to separate my receivers from my transceivers, and gain a somewhat better reception on MW and LW in the process. I spent large part of the day on the roof, playing around with various pieces of wire, and different ways to mount the stuff. I tried to run various end fed wires across the roof, close to my dipoles. Bad idea. The new antenna had a negative influence on the RX/TX dipoles, which resulted in a horrible SWR on 40 meters. Reception wasn’t impressive either.
Next I tried a 20 meter long sloping wire, also end fed, from the top of the roof to the back of my garden. That worked out better, but the amount of (man made) noise was insane. Some of the interference went away after proper grounding, but it’s still far from ideal.
A simple dipole, 2 x 20 meters, proved to be the best system here. Hardly any interference, and a good reception. Tomorrow I will construct a test version of an open dipole, made from quality materials, and figure out the best place to run the wires. Still wondering about a folded one though.