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brushed or brushless?

If you are new to this hobby, and especially to small quadcopters, you should understand the difference between brushed and brushless motors.

Brushed motors have been invented long time ago. They use a simple mechanical process (a "commutation") to move the magnetic field that turns the motor shaft. A brushed motor can be operated with a simple low voltage constant voltage source, e.g. a battery.

Brushless motors do not have an internal system to rotate the magnet field. A brushless motor is more efficient and can create more power (per weight) than a brushed motor. A brushless motor relies on an external computer (ESC, electronic speed controler) to generate a 3-phase signal to modulate the power supply.

Considering palm sized micro quads, the key differences between brushed and brushless motors are:

- supply voltage range / battery requirements
brushed motors can deliver useable power with 3-4V (1S) voltage
brushless motors typically need higher voltages (11V+) (3-5S) to deliver peak performance
-> batteries for brushless micros tend be to larger and heavier

- speed control requirements
brushed motors require a simple MOSFET (integrated on the flight controller) to control power
brushless motors require an external ESC board between flight controller and motor
-> electronics for brushless micros tend to be larger and heavier

- inrunner/outrunner
brushed motors are inrunners, they are easy to mount
brushless motors are usually outrunners, they are difficult to mount

With brushed motors, its easy to build a harmless 30g quad that can comfortably be flown indoors and is safe for kids, pets and property. Once you get to an open field, a 30g quad gets a bit too slow, you need more momentum to fly faster and higher.

With brushless motors, it makes more sense to aim for a target weight of at least 50g. If you build lighter than that, components will be difficult to get, parts will be unreliable, and construction will be difficult. For a 80-100g brushless micro you will get plenty of parts, it will fly a LOT faster than a 30g Whoop and can be a serious weapon in the park or on the race track, but it is not advised to fly this near people or property, and its probably not a good beginner quad.

TLDR: Brushless motor create more power, but they require more electronics and higher voltage to operate, so you usually en up with a heavier and more powerful machine. A 80g brushless quad is a lot faster, and has significantly more potential to hurt someone compared to 30g.

You also need to learn about the 2.4GHz RC link to control your copter! Read on..

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