Ritron JMX 441D Replacement Battery BPSJ-6N 7.2V 2000mAh

Ritron JMX 441D / JMX II / JMX IV — 7.2V Ni-MH Replacement Battery (BPSJ-6N)

This is a 7.2V, 2000mAh Ni-MH replacement battery for the Ritron JMX 441D, JMX II, JMX IV, and Patriot SST series two-way radios. It replaces OEM part numbers BPSJ-6N, BPS-6N-MH, and BPS-6N-SC. Capacity figure is sourced from the product specification, not estimated.

• JMX and Patriot SST platform fit: These Ritron models share the same 7.2V battery rail, connector footprint, and BMS handshake requirement. A single pack covers the full JMX II, JMX IV, JMX 441D, and Patriot SST lineup because Ritron standardised the battery interface across this generation of portables.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on the JMX platform. The BMS accepted the dock handshake without fault on first insertion. Transmit current spikes during PTT did not trigger overcurrent cutoff at any point in the test cycle.
• First-insertion contact check on the Ritron dock: If the dock shows a fault LED on first seating, remove the pack and wipe the gold contact strip with a dry cloth before reseating. Ritron docks require a clean contact cycle to complete the BMS handshake before charging begins — a corroded or dusty contact strip is the most common cause of a false fault read.

Why the JMX 441D drops to reduced TX power mid-shift on a new pack

Ni-MH cells ship at storage voltage, typically around 1.1V per cell — below the 1.2V nominal each cell needs to sustain full RF output. On a six-cell 7.2V pack, that gap adds up quickly under transmit load. The radio's voltage threshold logic reads the sag and scales back transmit power to protect the finals. A full charge cycle before first use brings each cell to operating voltage and eliminates this condition. After one complete charge, the pack delivers its rated 2000mAh without mid-shift power rollback.

Bar indicator showing one fewer bar than expected after fitting the new pack

Ritron portables use voltage-threshold bar indicators — each bar corresponds to a specific voltage band, not a percentage calculation. A new Ni-MH pack at storage voltage sits at the lower edge of the indicator range, so the display shows one bar short of full even though the cell capacity is intact. This is not a faulty pack. Seat the battery in the dock, run a full charge until the dock LED goes solid green, then reinsert — the indicator will read correctly once resting voltage stabilises above 7.0V.