About this replacement
Samson Swar2 Airline / Micro AR2 — 3.7V Li-Polymer Replacement Battery (1-OTH0157)
This 3.7V, 300mAh Li-Polymer cell replaces the OEM pack in the Samson Swar2 Airline wireless headset and the Micro AR2 receiver. Both units share the same 1-OTH0157 cell and connector footprint. The Swar2 Airline is a UHF wireless headset used by performers and presenters who cannot afford a mid-show power drop.
- Swar2 Airline and Micro AR2 compatibility: Both devices run the same 3.7V rail with identical connector orientation and BMS handshake protocol — one cell covers both units without modification.
- Bench tested on actual hardware: We cycled this cell through the Swar2 Airline's combined UHF transmission and audio draw. The BMS held stable voltage across the full discharge curve and tripped cleanly at the low-cell threshold without dropping mid-transmission.
- First charge in the transmitter body: Insert the new cell into the Swar2 Airline body and run one complete charge cycle before use — the headset's internal BMS needs a full cycle to calibrate its capacity register. Skipping this step causes the charge indicator to misread remaining capacity from the first session.
Why the Swar2 Airline cuts out mid-performance on a new battery
The Swar2 Airline draws simultaneously from the UHF transmitter and the audio amplifier circuit. Under that combined load, a cell at partial or storage voltage can sag below the BMS cutoff threshold even if the indicator shows charge remaining. A new cell shipped at storage voltage — typically 3.6–3.7V — has not been conditioned to deliver full current without sag. Running two to three full charge-discharge cycles brings the cell to rated capacity and eliminates mid-performance dropout caused by voltage sag.
Charge indicator reads full but headset shuts off after a few minutes
This happens when the BMS capacity register still holds the degraded profile of the old cell. The register reports "full" based on stale data, but the new cell's actual discharge curve does not match. A full charge from flat — down to the BMS low-voltage cutoff at approximately 3.0V, then charged uninterrupted to 4.2V — forces the register to rewrite. After one complete cycle the indicator tracks correctly against the new cell's actual state of charge.