About this replacement
Peterson BBS-1 BodyBeat Sync — 3.7V Li-ion Replacement Battery (YT423441)
This 3.7V, 700mAh Li-ion cell replaces the internal battery in the Peterson BBS-1 and BBS-1 BodyBeat Sync Wireless Pulsating Metronome. The BBS-1 is a wearable wireless metronome — a body-worn pulsating device used by musicians to feel tempo rather than hear it. When the original cell degrades, pulse output weakens or stops; this replacement restores full operation.
- BBS-1 and BodyBeat Sync compatibility: Both devices share the same PCB voltage rail, connector footprint, and BMS handshake threshold. The YT423441 cell matches all three, so the unit powers on and communicates with the transmitter without re-pairing.
- Bench tested on actual hardware: We cycled this cell through transmit-and-receive sequences on the BBS-1 platform. The BMS held cutoff cleanly at the low-voltage threshold — no false low-battery flags, no mid-session shutdowns.
- Wireless sync tip for the BBS-1: After swapping the internal cell, the BBS-1 and its paired transmitter may lose sync. Power both units off completely, replace the battery, then power the transmitter on first before the receiver to force a clean re-pair handshake.
Pulse output weakening before low-battery indicator triggers on the BBS-1
The BBS-1 drives its vibration motor and wireless receiver simultaneously. As the Li-ion cell ages, internal resistance climbs — voltage sags under the combined draw even though open-circuit voltage still reads acceptable. The BMS logs the cell as adequate, but the motor driver sees insufficient voltage and reduces pulse force. Replacing the cell at the first sign of weak pulse — rather than waiting for the indicator — prevents missed beats mid-session.
Receiver not syncing to transmitter after internal battery swap
Pulling the internal cell cuts power entirely, clearing the receiver's paired-device memory on some BBS-1 units. When the new cell goes in and the receiver boots, it scans for a transmitter signal but finds nothing if the transmitter is still off or mid-boot. Power the transmitter first, wait for its status LED to stabilise, then power the receiver. If sync still fails, hold the pair button on the transmitter until the receiver LED confirms lock — typically within 5 seconds.