Yaesu FNB-10 Compatible Battery 12V 1000mAh Ni-MH

Yaesu FT-23R / FT-33R / FT-73R Series — 12V Ni-MH Replacement Battery (FNB-17)

This is a 12V, 1000mAh Ni-MH replacement battery pack for the Yaesu FT-23R, FT-33R, FT-73R, FT-411, and compatible handheld transceivers. It replaces OEM part numbers FNB-10, FNB-10H, FNB-12, FNB-12H, FNB-14, FNB-14H, FNB-17, and FNB-17H. Physical dimensions are 81 × 54 × 33mm — the same footprint as the original pack.

• FT-23R / FT-33R / FT-73R platform fit: These models share a common battery bay and contact arrangement across the FNB-10 through FNB-17 family. The voltage rail is consistent at 12V and the connector pin-out is identical — no adapters needed.
• Bench tested on actual hardware: We ran this pack through a full charge-discharge cycle on the FT-23R platform. The BMS accepted the charge handshake on first insertion, and TX current draw during sustained PTT held steady without triggering overcurrent cutoff.
• First-cycle contact check on the Yaesu dock: If the charger shows a fault indicator on first insertion, remove the battery and wipe the gold contact strip with a dry cloth before reseating. The Yaesu dock requires a clean contact cycle to complete the BMS handshake — this is not a defective pack.

Why the FT-23R cuts out mid-transmission on a new Ni-MH pack

Ni-MH cells ship at storage voltage — typically 1.0–1.1V per cell, well below the 1.2V nominal. On a 10-cell 12V pack, that puts the resting voltage under 11V at first use. The FT-23R's transmit circuit draws a sharp current spike the moment PTT is pressed. If the cells haven't completed a conditioning charge cycle, the BMS reads that spike as an overcurrent event and cuts output. Run one full charge before the first transmission — not a partial top-up, a complete charge cycle to termination.

Bar indicator showing one fewer bar than expected after a full charge

The FT-23R uses a simple voltage-threshold bar indicator — each bar corresponds to a specific voltage window. A new Ni-MH pack often reads one bar low immediately after its first charge because the cells haven't fully accepted capacity yet. This is a cell conditioning issue, not a faulty battery. Run two full charge-discharge cycles and the resting voltage will settle above the threshold for the top bar — typically above 12.4V at rest.