Ham Radio op here. Yes, it's a HF antenna. To be more specific, it's a multi-element beam so it's directional. If if was actually used by most ham operators, it would have a motor at the top of the tower to turn the beam toward the signal. I don't see a motor in this one, so it's fixed in one direction. Ham Operators aren't the only users of the HF bands - it's shared with ship-to-shore marine, military, oceanic aircraft, and many shortwave broadcasters.