ZTW Backup Capacitor 25F 6V-8.4V 25A Receiver Power Backup for RC Helicopter, Airplane and Fail-Safe Servo Power

Automatic Receiver Power Backup

If the ESC's BEC drops out or the main battery fails mid-flight, the Backup Capacitor instantly takes over, supplying power to the receiver and servos so the pilot retains control and can land safely instead of suffering a total flyaway or crash.

25 Farad Capacitance

The 25F supercapacitor bank stores enough energy to power standard receiver and servo setups for approximately 20-30 seconds depending on servo count and load — sufficient time to autorotate a helicopter or glide a fixed-wing to a safe landing.

6V-8.4V Input for 2S HV Systems

Designed for 6V to 8.4V BEC systems (max 9V), matching 2S LiFe, 2S LiHV, and high-voltage 7.4V/8.4V BEC setups common in 500-700 class RC helicopters and larger airplanes.

Two Activation Modes

The 3-pin orange signal wire supports two control methods: switch mode (manual arming via a transmitter channel) or automatic throttle-signal mode (50-600Hz detection), allowing flexible integration with different radio systems.

25A Burst Output

Delivers up to 25A instantaneous output to cover high-current servo spikes during control surface deflection, ensuring servos do not brown out even under heavy aerodynamic loads.

Compact 41g Package

At 60×36×23mm and 41g with a 60-core silicone JR lead, the unit mounts easily on a helicopter frame tray or inside a fuselage without significant weight penalty.

Fail-Safe for Professional Platforms

Beyond RC sport flying, the Backup Capacitor provides an additional layer of power redundancy for commercial UAVs and professional aerial platforms where a BEC brownout could result in equipment loss or mission failure.