EADS TPH700 HR7742AAA02 Replacement Battery 7.4V 1800mAh

EADS TPH700 / P3G — 7.4V Li-ion Replacement Battery (HR7742AAA02)

This 7.4V 1800mAh Li-ion battery replaces the OEM pack on the EADS TPH700 and P3G portable two-way radios. It matches the original voltage rail and connector format, and slots directly into the radio body without modification. OEM part numbers HR7742AAA02 and HR7742AAB02 are both covered by this replacement.

• TPH700 and P3G platform fit: Both models share the same battery bay geometry, contact layout, and 7.4V nominal voltage requirement. The BMS in this pack is tuned to the same communication handshake the dock and radio expect on power-up.
• Bench tested on actual hardware: We ran this pack through full charge and discharge cycles on the TPH700 platform. The BMS tripped correctly at low-voltage cutoff and accepted recharge without fault flags on the dock LED.
• First-insertion contact check: If the charger dock shows a fault LED when you first seat this battery, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The TPH700 dock requires a clean contact cycle to complete the BMS handshake before charging will begin.

Why the TPH700 cuts out mid-transmission on a new battery

When you key PTT, the radio draws a sharp current spike to power the RF transmit stage. If the BMS detects this spike as overcurrent — which can happen in the first few cycles before the cells settle — it trips the protection circuit and kills output. This is not a faulty pack; it is the BMS acting on an unfamiliar impedance profile. Run two or three full charge and discharge cycles to let the cells stabilise, and the BMS will stop tripping on transmit current.

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

New Li-ion cells ship at storage voltage — typically around 3.7V per cell, not the 4.2V of a full charge. The TPH700 reads voltage thresholds to set the bar count, so a pack at storage voltage will show one or two bars even though the cells are healthy. Charge the battery to full in the dock before the first use. Once the pack reaches full charge voltage, the indicator will read correctly.