BD139 Push Pull Amplifier Experiments - Part 1

Video looking at some initial experiments with a BD139 based push pull amplifier. The aim of the experiment was to kick off a discussion in order to gain a better appreciation of how these types of amplifiers are designed, and what realistic power could be obtained from the BD139. The video is essentially a collection of data and makes no definitive conclusions. Constructive feedback is more than welcome. I have just checked the BD139 spec sheet and I see the VCE(sat) is 0.5V. I should have used that in the RL calculations.