Yaesu SBR-14 FT-3D Replacement Battery 7.4V 2000mAh

Yaesu FT-3D / VX-8R Series — 7.4V Li-ion Replacement Battery (SBR-14)

This is a 7.4V, 2000mAh Li-ion replacement for the Yaesu SBR-14 / FNB-102LI battery pack. It fits the FT-3D, FT-8DR, VX-8R, and VX-8DR handhelds. Drop this in where the original pack lives — same voltage, same footprint, same connector orientation.

• FT-3D / VX-8R platform fit: These models share the same 7.4V two-cell battery bay, connector pinout, and BMS handshake protocol. One pack covers the entire family because the charging dock reads voltage and thermistor data from the same contact strip across all four variants.
• Bench tested on actual hardware: We ran this pack through charge and transmit cycles on the FT-3D dock. The BMS accepted the initial handshake without a fault LED, held stable voltage through sustained PTT presses, and the protection circuit tripped correctly at the low-voltage cutoff threshold.
• First insertion on the Yaesu dock: If the dock shows a fault LED on first seating, remove the pack, wipe the gold contact strip with a dry cloth, and firmly reseat it. The Yaesu dock requires a clean contact cycle to complete the BMS handshake before it will begin charging.

Why the FT-3D cuts out mid-transmission on a fresh battery

A PTT press on the FT-3D pulls a hard current spike — often 1.5A or more — in the first millisecond of transmit. A new pack sitting at storage voltage (typically around 3.7V per cell) has higher internal impedance than a fully charged cell. That impedance causes a voltage dip sharp enough to trip the BMS overcurrent circuit before the RF output even stabilises. Charge the pack to full before the first transmit session — internal impedance drops significantly above 4.0V per cell — and the cutout stops.

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

The FT-3D uses a simple voltage-threshold bar indicator, not a fuel gauge chip. A new cell delivered at storage voltage reads lower than a cycled pack at the same state of charge, so the radio maps it to a lower bar tier. Run one full charge-and-transmit cycle and the cell voltage rises to its nominal curve. After that first cycle, the bar count aligns with actual charge level — typically reading full at or above 8.2V pack voltage.