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The poor performance of the Comet on the vertical side almost makes it just worth putting up a 3 element horizontal. It is quite possibly the most difficult antenna to set the vertical VSWR on. When you manage to get it acceptable, the amount of coax and mast radiation on the vertical side makes the performance just about acceptable if it doesn't plague you with RFI first. Chokes on the coax and mast isolation don't do much at all to help this antenna because we are not dealing with common mode currents. It's parasitic excitation from being right on top of the driven element. In fact, they are so close I'm sure there is some degree of capacitive coupling taking place too. Y Quad or Shooting Star if vertical is important.

[QUOTE="Shockwave, post: 400816, member: 10882"] The poor performance of the Comet on the vertical side almost makes it just worth putting up a 3 element horizontal. It is quite possibly the most difficult antenna to set the vertical VSWR on. When you manage to get it acceptable, the amount of coax and mast radiation on the vertical side makes the performance just about acceptable if it doesn't plague you with RFI first. Chokes on the coax and mast isolation don't do much at all to help this antenna because we are not dealing with common mode currents. It's parasitic excitation from being right on top of the driven element. In fact, they are so close I'm sure there is some degree of capacitive coupling taking place too. Y Quad or Shooting Star if vertical is important. [/QUOTE]

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