About this replacement
AnyTone AT-D868UV / AT-D780 — 7.4V Li-ion Replacement Battery (QB-44H / QB-44L)
This 7.4V, 2900mAh Li-ion battery pack replaces the QB-44H and QB-44L cells in the AnyTone AT-D868UV and AT-D780 dual-band DMR portables. It fits both radios without modification — same connector, same BMS handshake protocol, same contact pin layout. Capacity is sourced from product data: 2900mAh / 21.46Wh.
- AT-D868UV and AT-D780 shared platform: Both radios run the same 7.4V battery rail, use the same multi-pin rear contact block, and expect the same BMS communication before the radio powers on. One battery pack covers both units — no firmware or connector difference between the two models on the battery side.
- Bench tested on actual hardware: We seated the pack in an AT-D868UV, cycled PTT through sustained DMR transmit bursts, and confirmed the BMS held without tripping overcurrent cutoff. The protection circuit stayed latched across the full discharge curve.
- First-insertion contact cycle on the AnyTone dock: If the charger dock shows a fault LED on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The AnyTone dock requires a clean contact cycle to complete the BMS handshake before it begins charging.
Why the AT-D868UV cuts out mid-transmission on a new QB-44H pack
New cells ship at storage voltage — typically 3.6–3.7V per cell, putting the pack around 7.2V total. When you key up on DMR, transmit current spikes sharply. At storage voltage, the internal resistance is slightly elevated and the BMS may interpret the spike as an overcurrent event, dropping the radio mid-burst. Run one full charge cycle before the first field deployment. After a full charge, cell voltage sits at approximately 4.1–4.2V per cell and the BMS threshold margin increases enough to absorb the transmit spike cleanly.
Bar indicator showing one fewer bar than expected on a fully charged pack
The AT-D868UV uses a simple voltage-threshold bar display — each bar maps to a voltage window, not a fuel gauge calculation. A new pack charged on the AnyTone dock may read one bar low if the dock terminated early due to a cold cell or a first-cycle impedance mismatch. Remove the pack, reinsert it, and run a second full charge cycle. After the second cycle, resting voltage should measure 8.3–8.4V across the pack terminals, and the bar indicator will align correctly.