Comet GP-6
$$$··
| Frequency | 144-148 / 440-450 MHz |
| Gain | 6.5 (2m) / 9.0 (70cm) dBi (manufacturer figures; 2x 5/8-wave on 2 m, 5x 5/8-wave on 70 cm) |
| TX power | 200 W (200 W SSB / 100 W FM) |
| Modes | FM, SSB, CW, digital |
| Connector | SO-239 |
| feedpoint | SO-239 at the base |
Estimated (unverified): introduction year (1990s-2000s, long-running model)
Top-of-line gain from the GP family without exotic pricing: 6.5 and 9.0 dBi is a real, audible step over the mid-size class, and the rest of the recipe stays reassuringly boring - sealed fiberglass, SO-239, no radials, nothing to tune. The two-section design keeps shipping and handling manageable for a ten-foot antenna.
Ten feet of fiberglass is a structural commitment: wind load and leverage demand a proper mast and bracket, and the flattened high-gain pattern that helps on flat terrain works against you when repeaters sit well above or below the horizon. FM rating is half the SSB figure, and the compact siblings cost half as much.
The GP line's flagship for operators who have the mast for it: maximum family gain, same zero-maintenance philosophy. In flat country with a solid mount it is the obvious step up from the mid-size class; in the hills or on a push-up pole, buy shorter.
The GP-6 is what happens when the GP recipe is allowed all the height it wants: ten feet two inches of sealed fiberglass in two sections, two phased 5/8-waves on two meters and five on seventy centimeters inside, and the family's signature absence of radials, traps, and tuning. The published numbers — 6.5 dBi on two meters, 9.0 on seventy centimeters — put it a clean step above the mid-size class, and the 200-watt SSB rating carries over unchanged.
Height is the whole bargain. Ten feet of radome adds real gain and real wind load in the same stroke, so the mounting hardware stops being an afterthought: the 30-to-62-millimeter clamp range matches the smaller models, but the mast behind it needs to be honest steel, well guyed or well bracketed. And the taller the collinear, the flatter its pattern — superb across flat country, less helpful where the terrain puts repeaters far above or below your horizon. The physics is the same lesson the tall mobile whips teach, at base-station scale.
Within the family, the GP-3 gives up about two decibels to save four feet and half the money — the sensible default — and the GP-1 is the stealth pick. The direct cross-brand rival is the Diamond X300A, another ten-footer with near-identical claims; the two split club towers the way their smaller siblings split home rooftops. Dealer copy pitches the GP-6 for repeater duty, and that is where many of them live.