I see....
For 4 years I used nothing but a Carolina Windom cut for 40M. With a tuner, either in the radio, or external, it works all bands from 40 thru 6. At 35 feet high and about 66 ft long, it gave me the ARRL TPA award, WAS in one RTTY contest, 180 DXCC countries, etc. It was cheap and easy and fit in my yard.
For several of those years, I tried to get it to work on 75/80M as well but it would not.
Then I see that Radio Works, who sells the commercial version of these, has what they call a "compact 80M version---still only 66 feet long. Runs any band from 80-10/6.
Essentially, it is the 66' forty version with a set of Drooping extensions that hang down below the main wire and get attached to the center insulator with about a 5' pc of nylon paracord. So the extended sections make it about 130 ft of wire .
THis is NOT a folded dipole. I dont think a folded dipole is any shorter but is more broadbanded and has a different feedline impedance than a normal dipole--in a folded dipole the main wire is continuous across the center and feeds at the center of the second.
Anyway, I tried adding the drooping extensions to my 40M windom and it works pretty well. I think it has altered the operation on the higher bands but they still all work. It is a little fussier to tune but works. With the MN-7000, I am able to get it to 1:1 nominal across the entire band although there are bands that will not tune using the internal tuners on most of my newer radios.
If you do this, use a good coax line choke or two as RF in the shack can be an issue. Also know that Tuning thru coax is a lossy proposition--when the SWR in the shack says 1 to 1, the coax is still running miss-matched by a lot in some cases. But the antenna will work.
To try out a simple test, just take a regular dipole cut for 75/80M--hang the part you can stretch out and let the rest bend, fold, turn or whatever. You might have to adjust it in length, but it will work.
Or use a vertical....
Curt
KU8L