A remote tuner will work the best, but if you don't have or can't buy one, then a 9:1 unun will work. It's not perfect, but it will get the antenna's impedance down to a livable level, where losses won't be much of a problem if you use good quality coax (RG-8 or better).
A wide-range in-shack tuner will be required; the tuner in the rig must be turned off. Your antenna will have to be at least 1/4 wavelength long at the lowest frequency to be used, but in no case should it be a multiple of 1/2 wavelength on any band. 43 feet is a good length for 40-10 meters, but it's not a "magic number." 80 feet or so should be OK if you want to include 80/75 meters.
Treat it like a vertical. It will have to be worked against a good ground system -- either a large number of buried radials (32 or more preferred, 16 minimum, each the length of the antenna if possible), or if they are elevated, even by a couple of feet, two 1/4 wl radials per band. I use one radial per band in my system, but two should work much better. A single radial will radiate, which is something you may not want. But you must use a radial system of some kind. The coax shield alone will give you problems (poor performance, RF in the shack, etc.).
Experiment, and see what you can do. An antenna analyzer is all but mandatory when experimenting with antennas. You'll see exactly what you need to get a good match on all desired bands.
Have fun!
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Topic: coax feed to random wire antenna (Read 4568 times)