Watermelon is one of fruit that consist of 90 % water with difference characteristics as red and yellow, seed or not. Farmers or sellers have some method to know the characteristic of watermelon by hitting watermelon to make a sound. It can identify quality of watermelon The sound can decided characterictic watermelon that is rip or not, with characteristic amplitude from the sound. Mic pre-amplifier received the sound to detect analog to digital converter before Microcontroller AVR ATMega 8535 . ATMega 8535 AVR microcontroller is used to store several types of sound used to determine the quality of watermelon. The result is displayed the LCD and LED Keyword: mic � pre amplfier, microcontroller AVR ATMega 8535, LC
