RadioLink AT9S Pro Instruction Manual page 15

PRM-01 shows real-time model Voltage. When the voltage is low, the transmitter will vibrate with beep sound.
And there is text prompt on the screen. The flight will be safer.
PRM-03 Real-time OSD information telemetry module
Real-time model data allows users to receive crucial information on the model's systems. With flight module
PRM-03 and flight controller PIXHAWK/Mini Pix/TURBO PiX, model voltage, speed, climb, throttle, longitude,
latitude, altitude, GPS, RSSI, flight mode, yaw, roll, pitch, and distance are display on the transmitter screen.
Telemetry modules are sold separately. You can enter the Aliexpress Official Store to purchase. Or login to
the RadioLink official website for product details.
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