Changes
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RC9 includes the following changes:

- patches for MIMO and Coverage functions on the Ralink dual band radio.
- TxPower is not set by default - the field is blank.
- USB Modem WAN operation

Default AP and Mesh Operation
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RC9a defaults to AP and Mesh operating on the main 2.4GHz radio on Channel 1.

RC9b defaults to AP  operating on the main 2.4GHz radio on Channel 1 and 
the Mesh operating on the dual band radio on Channel 157.

RC9c includes support for USB 3G/4G modem operation.

TxPower Setting
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The parameter is not set by default, which means that the radios will use the driver default setting, 
which is the maximum power setting for the selected channel.

The power level used will be reported in the SECN Advanced page.

To adjust the power level simply enter an appropriate value in the field, Save and restart.

The TxPower level for the main AR9331 radio can be set to 0 - 18 and this is approximately the dBm output.

The TxPower level for the secondary Ralink radio can be set in the range 0-30, depending on the selected channel.
There is not a simple relationship between the set value and the actual power output.
Not all TxPower values in the nominal range can be used on all channels.
The reported power does *not* reflect the actual dBm power level, just the setting that is used.
The maximum actual output power is ~18dBm and is available on the higher channels (149 and above)