Abstract:
PPM - service learning activities aims to apply the results of research on onion crop productivity improvement as a strategic horticultural products through bioharmonic audio system design as a natural growth stimulator frequency based local animals. Particular purpose, are: (1) promote environmentally friendly technology are cheap and can improve productivity and speed up the onion crop harvest through community service in bukent corruption so that the resulting field of audio engineering and modification technologies bio harmonic system; (2) for the region contribute to community development programs PPM - based service learning fun and have significant benefits for students, the community and onion farmer partners; (3) obtain accurate data on the use of variable frequency acoustic waves and sound intensity level that has special characteristics for onion crop, thus increasing the productivity of onion based indicators of yield and growth rate of onion plants from the aspects of morphology as well as shorten the harvest period.
The design activities used are workshop and assisting in the creation and application of appropriate technology bio- harmonic audio source (ABH) with variable audio frequency change (f) 200 Hz - 500 Hz sound intensity and extent of 0 dB - 120 dB corresponding to the growth and onion crop productivity. Electronic circuit blocks including the source ABH SWG (Square Wave Generator) which form an astable multivibrator to produce a square wave. Number 7 SWG that each - each issued a fundamental frequency of 2000 Hz, 2500 Hz, 3000 Hz, 4000 Hz, 4500 Hz, 5000 Hz.
Activities undertaken in KKN - PPM has been able to realize these three objectives defined above which has managed to popularize the system bioharmonic audio technology to increase productivity and accelerate the opinion crop harvest through community service in the form of corrupttion. Percentage of team activities and the servants of corruption student activities that occur during the training process. Percentage of team activities devotees range from 10.5% to 35.5%. The most dominant team activity is explained training materials, namely 45% and 10% seek additional examples.while the activity is at least 4% provide feedback and to engage actively stimulate 5%. While the service learning student activity dominated by Listening/ attention explanation of the team coach or student else CCN 40% and at least 50% is to ask questions and write down the things that are important 10%.

Keywords: audiobio-harmonic system, onions, and community empowerment