This project is based on the TenaTester build by ZL1CVD.

Ressources:
 * https://learn.adafruit.com/adafruit-si5351-clock-generator-breakout/wiring-and-test
 * http://community.silabs.com/t5/Timing-Knowledge-Base/Modifying-Output-Driver-Strength-of-the-Si5351/ta-p/112253
 * https://github.com/etherkit/Si5351Arduino
 * http://images.google.de/imgres?imgurl=http://www.kh-gps.de/si5351_4.jpg&imgrefurl=http://www.kh-gps.de/si5351.htm&h=483&w=1115&tbnid=p6ACt2AabOao6M:&tbnh=90&tbnw=208&docid=YzcwWac64G4VOM&usg=__tpZeibmT-PYky-rOAt6f3X7w_7s=&sa=X&ved=0ahUKEwjggd_4tI_PAhUEnRQKHQHdAVUQ9QEIJzAC