Satlink F03409 DVB-S Signal Finder Replacement Battery 7.4V 3000mAh

Satlink WS-6902 / WS-6905 Series — 7.4V Li-Polymer Replacement Battery (F03409)

This is a 7.4V 3000mAh (22.2Wh) Li-Polymer replacement battery for the Satlink Data Satellite Signal Finder DVB-S Digital LCD range. It fits the WS-6902, WS-6905, and WS-6905 SE Version, along with over 29 additional compatible models in this finder series. The F03409 part number matches the OEM cell format and connector used across these portable satellite signal meters.

• WS-6902 and WS-6905 platform fit: Both finders share the same 7.4V bus, identical battery bay dimensions (88.20 × 64.70 × 8.90mm), and the same BMS handshake protocol — which is why a single F03409 cell covers the full range, including the SE variant with its extended signal logging firmware.
• Bench tested on actual hardware: We cycled this pack through the WS-6905 startup sequence and monitored BMS response during DVB-S lock acquisition. The BMS held stable across the inrush current spike at screen-on and tuner initialisation — no cutoff trips recorded during testing.
• Post-install calibration cycle: After fitting this battery, run a full signal scan cycle through the finder menu before heading to site. The instrument maps battery state during active operation, and skipping this step causes the low-battery indicator to fire early on the first field session.

Why the WS-6905 cuts power during DVB-S tuner lock

When the WS-6905 acquires a satellite lock, the tuner and LCD backlight draw current simultaneously — this brief combined spike can exceed the BMS overcurrent threshold on a degraded or deeply discharged pack. A new cell with full charge capacity absorbs this spike without tripping the protection circuit. If the finder shuts down at the moment of signal acquisition, the pack's internal resistance is usually the cause, not the tuner itself. Charge the replacement fully to 8.4V before the first use to give the BMS its widest operating window.

Finder powers on but shuts off immediately during USB data transfer to a PC

USB data transfer adds a sustained draw on top of the display and processor load — on a partially discharged pack, this combined current can push the BMS into protective shutdown within seconds of the PC connection. The finder may appear to have enough charge to operate normally, but the voltage sags below the BMS cutoff threshold the moment the USB bus draws current. Charge the pack to at least 7.8V before running any PC transfer session. If the unit still cuts out at that level, check the USB cable — a resistive cable increases draw-side voltage drop and compounds the problem.