Comet SBB-5NMO Dual-Band Mobile vs HYS 21-inch NMO Kit with L-Bracket

The Comet SBB-5NMO is the stronger performer here. At 965 mm, it achieves a half-wavelength on VHF (0.47 wavelengths), which is the electrical sweet spot for mobile antennas and yields realistic 3.4 dBi gain without ground plane dependency. On UHF it runs longer but still delivers 5.2 dBi. The HYS 21-inch is compromised on VHF at just 0.26 wavelengths, producing only 2.2 dBi and relying heavily on your vehicle's ground plane to work properly. HYS also overstates its gain at 2.15 dBi claimed versus its actual electrical length.

The critical differentiator is VHF electrical length. The Comet's half-wave design on 146 MHz is fundamentally superior to the HYS quarter-wave approach, which requires a good ground plane to function and will underperform on vehicles with poor grounding.

The Comet SBB-5NMO suits users who want solid dual-band performance without ground plane worries. The HYS works best on vehicles with excellent metallic surfaces and for budget-conscious buyers prioritizing UHF over VHF capability.

Buy the Comet SBB-5NMO. It delivers better electrical design across both bands at a reasonable price, and owners report accordingly.