About this replacement
Stageclix Jack V3 / V4 Transmitter — 3.7V Li-Polymer Replacement Battery (LFT952245)
This 3.7V, 700mAh Li-Polymer cell replaces the original LFT952245 battery in the Stageclix Jack V3 and Jack V4 wireless transmitters. It restores wireless audio transmission when the original cell has degraded and can no longer hold a usable charge. Voltage and connector match the OEM spec exactly.
- Jack V3 and V4 compatibility: Both transmitter generations use the same LFT952245 cell format, voltage rail, and connector pinout. The BMS handshake behaviour is identical across the two, so one replacement cell covers either unit without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench, monitoring BMS cutoff thresholds and confirming the protection circuit trips correctly at low voltage. Cell voltage at rest settled at 3.85V between cycles, consistent with a healthy Li-Polymer pack.
- First-cycle base station logging: On first use, dock the transmitter in the base station and allow a complete charge cycle before making a call. DECT-based wireless systems log the new cell during that first base-station cycle — skip it and the talk-time counter will read inaccurately until the log updates.
Why the Jack V3 drops audio mid-transmission on a fresh battery
The Jack V3 draws from the cell simultaneously for the audio circuit and the DECT radio — two loads running in a compact housing with no thermal headroom. On a new cell that hasn't completed its first full base-station cycle, the BMS can misread the state of charge and trigger a low-voltage cutoff prematurely. The transmitter drops out not because the cell is empty, but because the protection circuit acts on an uncalibrated reading. A full dock cycle corrects the BMS reference point and the cutouts stop.
Base station shows a charging error after fitting the new cell
When a new Li-Polymer cell arrives at storage voltage — typically around 3.70V to 3.75V — some base stations flag it as a fault rather than initiating a charge cycle. The base expects to see a cell already within its normal operating window. Remove the transmitter from the dock, wait 30 seconds, then re-dock. If the error persists, check that the transmitter contacts are clean and seated flush — a partial connection causes the same error as a BMS handshake failure.