====== Duty Cycle ======

  * To remain within the IR2030 rules for a licence exempt short range transmitter we can only use 100mW with a duty cycle of 10%. It will be necessary to limit the nodes incase they receive too much traffic and stray over this duty cycle.

===== Average over time period =====
  * Could measure the length of the longest packet possible (full 64 chars).
  * Everytime the node transmits it adds this to a variable.
  * If in a certain time period (1 minute) it exceeds the duty cycle it stops transmitting until it drops back down below the 10%