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Range and failsafe check ?

Work through the checks with a helper at the model. Tick each one off as you go - the timer keeps track of the radio's range check mode.

Range check timer

Futaba's range check mode switches itself off after 90 seconds - the timer keeps track on any radio, and beeps at the end.

1:30

Range check

Failsafe check

Finding the range check mode

FrSky (ETHOS, ACCESS, ACCST)
Range check is in the model's RF / receiver settings. The radio drops to low power until you switch it off.
Futaba
Use the range check (power-down) mode from the menu - it lasts 90 seconds. Your radio's manual shows where it is on your model.
Spektrum
Range Test in the System Setup or Model Setup menu (older radios: hold the trainer button). Spektrum suggests about 30 paces (28 m).
ExpressLRS
There's no range check mode. Many pilots set the lowest output power (10 or 25 mW) in the ExpressLRS script for the test - and put it back afterwards.
Other radios
Look for 'range check', 'range test' or 'power down' in the manual, with the distance it expects.

How it works

A range check runs the radio at reduced power on the ground. If the link holds at 30 paces like that, it has plenty in reserve in the air. Do one with every new model, after a crash or a receiver change, and at the start of the season.

The failsafe check makes sure the model does something safe if it loses the signal - above all, the motor stopping. Most clubs expect electric models to cut the motor on failsafe.

The timer and ticks stay on this page only - nothing is saved.

Keep every model's numbers in one place RC Flyer Pro is a free logbook and hangar for RC pilots: your models, batteries, flights and flying field, with GPS flight replays in 3D. Start free

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