It's not possible to modify the power level of the Bluetooth module transmitter via software; however, the power level can be reduced by adding an SMA attenuator to the antenna or by removing the antenna altogether.
The following are approximate power levels with these different methods:
- Standard antenna: -50dBm
- Standard antenna w/ -20dB attenuator inline: -70dBm
- No antenna: -95dBm
Follow these steps to attach an SMA attenuator to the standard module antenna:
- Attach a reverse-SMA-to-SMA adapter to the antenna connector.
- Attach the SMA attenuator(s) to the reverse-SMA-to-SMA adapter.
- Attach an SMA antenna to the SMA attenuator, or attach the standard antenna to the SMA attenuator using a reverse-SMA adapter.