INSTRUCTION SHEET FOR ADVT-PRO-L « ADVT-PRO-M ADVT-PRO-H VHF WIRELESS TRANSMITTERS LOADING THE BATTERY: Remove the battery door (#1) and insert one 9 volt battery into the compartment, Check for correct polarity, MICROPHONE INPUT: Plug the EX-503 or similar lapel microphone into the. . input jack (#2) and extend the mic cable as much as possible for the best range. ON/STBY/OFF SWITCH: This slide switch (#3) is used to turn the transmitter to standby mode for auto activation or to on for manual operation.