* https://en.wikipedia.org/wiki/Frequency_allocation
  * MHz : 52 to 1088 : SdR
  * MHz : 3.2 : https://www.gearbest.com/tv-box-mini-pc/pp_188367.html?vip=2072514#
  * MHz : 433 :  https://www.youtube.com/watch?v=UDltH2nk5r0&app=desktop
  * Mhz : 446 : https://fr.wikipedia.org/wiki/PMR446
  * Mhz : 700-MHz to 2400-MHz : Cell / MobilE
  * Ghz : 2.4 : WiFi : or 5 GHz (these are unlicensed bands), 
  * Ghz : 3.4 to 3.8 : FrancE
  * Ghz : 3.8 : https://limemicro.com/technology/lms7002m/ 100kHz to 3.8GHz # SdR
  * Ghz : 6-GHz : 5G + mmWave
  * Ghz : 24 and millimeter-wave (mmWave) allocations opening above 24-GHz : 5G
  * Ghz : 26 GHz : Eu https://venturebeat.com/2019/05/15/eu-picks-26ghz-for-5g-millimeter-wave-requires-support-by-end-of-2020/
  * Ghz : 28 : https://www.gsma.com/spectrum/wp-content/uploads/2019/07/26-and-28-GHz-for-5G.pdf
  * Ghz : 100 (from 24) mmWave
  * Ghz : 300 Ghz : from 3 Ghz : MicroWave / SaT