I don't understand much how boosters work, but 105.5 WDBY (Patterson, New York) has (had?) a booster on 105.5 in Danbury, Connecticut that's supposes to help the signal in the Danbury area, but a guy I knew from Newtown (next town over from Danbury) showed me how in certain areas the main WDBY signal and the booster would interfere with each other and create a mess on 105.5 FM.