RadioRanked verdict
Comet
Comet GP-3 Dual-Band Base Vertical
One of the few antennas in this catalog whose advertised gain is exactly what the physics predicts. If you can put it up high, it will perform as advertised.
Proprietary RR score
How we scored it
Performance is derived from the antenna's length in wavelengths on each band it covers, not from the advertised gain. How we score →
Length versus wavelength
What 1803 mm Buys You
An antenna radiates according to its length measured in wavelengths, not according to the number on the packaging. Here is where this one lands on each band it covers.
| Band | Wavelength | This antenna | Works out as |
|---|---|---|---|
| VHF146 MHz | 2053 mm | 0.88 λ | full wave |
| UHF435 MHz | 689 mm | 2.62 λ | multi-wavelength |
Decision helper
Is this antenna right for you?
Yes, if you're…
- ✓A home or shack base station where you control mast height
- ✓Anyone who wants a gain claim they can actually verify
Skip it, if you're…
- ✕Portable or temporary setups (an NMO mobile whip is the right tool)
- ✕Anyone without a mast to mount it on
Tradeoffs
The good and the bad
What we like
- Published gain figures are independently verified by the antenna's own length
- Handles 200W, enough headroom for any handheld or mobile radio
- One-piece fiberglass radome, no field tuning
- Covers both 2m and 70cm off one feedline
What we don't
- Needs a mast (1.25-2.5 in) and coax, neither included
- $138 and 6 feet tall; this is a permanent installation, not a portable one
- Only 12 reviews, a thin sample for a base antenna at this price
Ready to buy?
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Overview
The Comet GP-3 is a fixed base vertical, 5 feet 11 inches (1803 mm) of one-piece UV-stabilized fiberglass, covering 2m and 70cm off a single SO-239 feed. It handles up to 200 watts and clamps onto a mast from 1.25 to 2.5 inches; you supply the mast, the coax, and somewhere to put it. This is a fixed installation, not something you carry.
Comet publishes 4.5 dBi on 2m and 7.2 dBi on 70cm, and this is one of the rare cases where the claim checks out: at nearly 2.6 wavelengths on 70cm, the GP-3 is a genuine phased collinear, and our length-based model independently lands at 4.4 and 7.1 dBi, within a tenth of a dB of Comet's own numbers. Height above the ground matters more than any of this, so mount it as high as your situation allows.
Specifications
| Frequency bands | VHF, UHF |
| Gain | 7.20 dBi |
| Connector | SO-239 |
| Length | 1803 mm |
| Antenna type | base |
| Flexible | No |
| size | Large |
| color | white |
| unitCount | 1 |
Key Features
- Dual-Band Coverage – Operates on both 2M (146 MHz) and 70cm (446 MHz) bands, providing versatile communication options for amateur radio enthusiasts.
- High Gain Performance – Offers 4.5 dBi gain on 2M and 7.2 dBi gain on 70cm, ensuring strong signal reception and transmission over longer distances.
- Durable Construction – Features a one-piece, heavy-duty, UV-stabilized fiberglass radome for long-lasting durability and reliable performance.
- High Power Handling – Supports up to 200 watts of power, suitable for various base station communication needs.
- Easy Installation – Includes clamp-on mounting hardware compatible with mast diameters from 1.25 to 2.5 inches, facilitating straightforward setup.
- Compact Design – Measures 5 feet 11 inches in height and weighs 2 pounds 12 ounces, making it suitable for installations where space is limited