1. More precise CW key timing
2. Lower the Tx audio gain, higher SNR for Tx
3. Add "MIC GAIN" option at menu [5/5] #3
   range=0-30, gain=0-15dB, step=0.5dB, default=20
4. Add "FACTORY RESET" option
   Press and hold "MODE" button when powering on
   Note: It's only reset the parameters to default,
   no effect to saved channels
5. Add AM transmitted function.