See also:

Audio operation precautions
Audio operation precautions ...

Regulatory Information
FCC Regulatory information – CAUTION: To maintain compliance with FCC’s RF exposure guidelines, use only the supplied antenna. Unauthorized antenna, modification, or attachments could dama ...

Battery
● Keep the battery surface clean and dry. Clean the battery with a solution of baking soda and water. ● Make certain the terminal connections are clean and securely tightened. χ ...