pxt-calliope/docs/reference/radio/set-transmit-power.md

Set Transmit Power

Sets the transmitter power for radio communications.
The power can be set to a value between 0 (-30dbm) and 7 (+4dbm).

Range

At power level 7, in an open area without significant interference (coming from WiFi networks or other devices operating on the 2.4 GHz range), you can get a range of over 70m.

Indoors (or with additional interference), range will be significantly reduced.

Important Security Consideration

The functions in the radio namespace allow the BBC micro:bit to communicate with other micro:bits.

This API does not contain any form of encryption, authentication or authorization. It's purpose is solely for use as a teaching aid to demonstrate how simple communications operates, and to provide a sandpit through which learning can take place.

For serious applications, BLE should be considered a substantially more secure alternative.

radio.setTransmitPower(1)

Parameters

• power -- a number between 0 and 7.

Example

Sets the transmitter power to full power at 7.

radio.setTransmitPower(7)

See also

receive number, send number, on data received