If you’ve ever needed a good antenna with a quick deploy when you are out portable, you can do a lot worse than using a vertical antenna. My configuration consists of a 9:1 UnUn no grounding spike connected to just over a 10m length of wire.
Ive used a similar deign in the pas that was using just under 10m and it worked really well on 17m. So well in fact that I was able to operate a Japanese station with 30w. (from an FT857D fitted in the car) tho sone is a not quite as good. The wire needs to be shorter, by how much i haven’t worked out yet. But i think that making it shorter by a couple of meters will be a good match for all bands between 40m and 10m.
Anyway here is a video of my exploits. Many thanks for all the stations i spoke with. I had quite a variation on signal reports, some excellent some very poor. And I’m not sure if that was band conditions or down to the antenna performance.