Charlie/NJ7V and Gaston/KT1RUN did a comparison of VHF antennas during a SOTA activation. Specifically, they compared a rubber duck antenna, a J-pole antenna on a tall mast, and a 3-element Yagi antenna. Spoiler Alert: the rubber duck sucks (they all do) but the Yagi and J-pole performed about the same.
Joyce/K0JJW and I use the Arrow 3-element Yagi antenna for most of our SOTA activations, so I am very familiar with that one. We also have a rollup J-pole that we use once in a while.
Charlie used the Yagi the same way we do: handheld at ground level. The J-pole was on a mast, maybe 12 feet (?) in the air. Although they were on a summit, there is some performance improvement getting the antenna higher than the surrounding terrain. The gain of the Arrow 3-element Yagi has been measured at about 6 dBd. The gain of a J-pole, being a halfwave radiator, is 0 dBd. The additional height of the J-pole has to make up this 6 dB of gain difference to be roughly equivalent.
A big difference, though, is that the Yagi antenna has to be held and pointed. The J-pole is always pointing in the right direction so you can just focus on operating and logging. We may have to consider using a omni antenna instead of the Yagi.
Good stuff!
73 Bob K0NR
Great article and certainly gives me reason to employ my homebrew J-Pole when on a SOTA activation. This issue is how to summit with a 12 foot mast to hold up the J-Pole. Certainly a collapsible Yagi has it’s advantages.
Many of the SOTA activators on HF use a fishing pole to support their wire antennas, typically end fed. You can use this same approach for holding up a rollup J-pole. These fishing poles are usually carbon fiber, very lightweight, extend to about 15 feet. Just strap it to a fence post, tree, stump, pile of rocks, etc.
Many vendors on ebay, here’s one example:
https://www.ebay.com/itm/3-6M-7-2M-Telescopic-Fishing-Rod-Stream-Carp-Carbon-Fiber-Hand-Pole-Freshwater/273986060061
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