Motorola P200 NTN4824A Replacement Battery 9.6V 1800mAh

Motorola P200 / HT600 / MTX800 Series — 9.6V Ni-MH Replacement Battery (NTN4824A)

This 9.6V 1800mAh Ni-MH battery replaces the original pack on the Motorola P200, P210, HT600, and MTX800 series portable two-way radios. It slots directly into the same battery bay and uses the same contact layout as the OEM pack. Also cross-references NTN5049A, NTN5414, NTN5447A, NTN5447B, NTN5521A, and NTN5531.

• P200 / HT600 / MTX800 platform fit: These models share a common 9.6V eight-cell Ni-MH architecture and identical battery bay dimensions. The BMS handshake on each radio accepts the same charge-acceptance signal, so one pack spans the full compatibility list without modification.
• Bench tested on actual hardware: We cycled this pack through full charge-discharge runs on the P200 and HT600 docks. The BMS held charge-acceptance voltage correctly through the conditioning cycle and showed no thermal anomaly under sustained PTT load.
• First-insertion contact check: If the charger dock shows a fault LED on first insertion, remove the battery and wipe the gold contact strip with a dry cloth before reseating. The Motorola dock requires a clean contact cycle to accept the new BMS handshake — this is not a fault with the pack.

Why the P200 cuts out mid-transmission on a freshly inserted battery

Pressing PTT on the P200 draws a short current spike as the RF output stage ramps to full power. A Ni-MH cell at storage voltage — typically 1.1–1.15V per cell — has higher internal impedance than a fully conditioned cell. That impedance causes a voltage dip across all eight cells simultaneously, and the radio's undervoltage protection trips before the transmission completes. Running one full charge cycle through the dock conditions the cells and drops impedance to normal operating range, which eliminates the cutout.

Bar indicator showing one fewer bar than expected on a new pack

The P200 and HT600 read battery level using a simple voltage-threshold circuit — each bar corresponds to a voltage window across the pack. A new Ni-MH battery ships at storage voltage, not peak charge voltage, so the radio places it one bar lower than it will read after a full charge. This is not a capacity defect. Charge the pack fully in the dock until the charge LED goes green, then recheck — the bar indicator will move to the correct position once the pack reaches 9.6V at rest.