In recent months I've been using a doublet hung from a gum tree fed with open wire feed line. To make it work on 80m I extended the ends in a "dog legs" back along the side fence lines. This arrangement works on 80m, 40m and 20m. While there are good reports of my transmission, reception has been very noisy, particularly on 80m.
This week I turned it in to a big loop by closing the ends and hanging them from the house.
It tunes up easily on 80m and 20m and with a little difficulty on 40m. Yesterday I did a lot of tuning around and listening and experienced very low noise with big signals. Today, I had a test QSO with Patrick, VK2PN who reported excellent signals from me, especially on 40m.
More detail: The loop is simple figure eight lamp flex (half) roughly joined with knots and screw terminals - this can be improved. 450 ohm slotted feeder runs down to the shed and is terminated with a 4:1 balun before the rig's auto-tuner.