Andrew Mcneil who normally does wifi based 2.4 / 5.8GHz videos this time looks into a typical mini quad vtx. A 200mW unit ( I don't think brand is mentioned ) is put through a soak test measuring its power output vs temperature.
Further testing using a poor man's liquid nitrogen and a heat sink.
! No longer available (http://www.youtube.com/watch?v=Ji2XZH6eFes#)