[FEATURE REQUEST] Increased BLE Transmit Strength for Repeaters using BLE during OTA

[KPrivitt]

Can the default value be changed to 8 to increase the BLE signal strength for repeaters that utilize the nRF52840 during an OTA firmware update?

The nRF52840 supports a transmit power level of up to 8 maximum.
bluefruit.h
// Supported tx_power values depending on mcu:
// - nRF52832: -40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +3dBm and +4dBm.
// - nRF52840: -40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +2dBm, +3dBm, +4dBm, +5dBm, +6dBm, +7dBm and +8dBm.

In the file NRF52Board.cpp OTA is initialized with a BLE power of 4 {line 283}

// Set max power. Accepted values are: -40, -30, -20, -16, -12, -8, -4, 0, 4
Bluefruit.setTxPower(4);

BLE is normally disabled in a repeater. In OTA mode BLE is enabled to allow for the transfer of the file during the "Over the Air" firmware update. Updating a repeater using BLE OTA eliminates the need to physically connect to the repeater (bring it down, reflash and return it, which can be "risky" on a highly slanted roof). The increased power can increase the range of the BLE connection (it may be high up on your roof).

The power utilization impact of the increased transmit signal is minimal since this mode is only used during a Firmware update. A low BLE signal level can slow the speed of the data transfer, an increase in transmit signal can improve speed and the success rate of an OTA update.