Nagoya NA-771 (SMA-Female) vs TIDRADIO TD-771 GMRS (SMA-Female)

The TD-771 GMRS is the clear winner for its intended purpose, but the NA-771 is the more versatile choice overall.

The most important differentiator is band coverage. The TD-771 is optimized for GMRS at 465 MHz where it achieves a genuine 5/8 wave electrical length and realistic 3.0 dBi gain. The NA-771 covers both VHF and UHF ham bands but compromises on both: it's electrically short on VHF at only 0.19 wavelengths (realistically -1.0 dBi) and merely adequate on UHF at 0.57 wavelengths. The NA-771's claimed 3 dBi gain is supported by its length, but that only applies to UHF.

If you operate primarily on GMRS, the TD-771 GMRS is the better antenna and costs half as much. If you need dual-band ham radio capability on both 2 meters and 70 centimeters, the NA-771 is necessary despite its VHF weakness, since no single handheld whip can optimize both bands simultaneously.

For most ham radio users wanting a versatile flexible whip, the NA-771 remains the pragmatic choice despite its score being lower than the GMRS-specific TD-771. The TD-771 wins only if GMRS is your primary or sole focus.