The first of the videos is ‘An introduction to Amateur satellites’ by David Johnson G4DPZ and Carlos Eavis G3VHF.
The PDF of the slides is here.
Other presentations are expected to be uploaded in the coming days.
Watch An introduction to Amateur satellites
PDF Slides of ‘An introduction to Amateur satellites’
AMSAT-UK videos on YouTube https://www.youtube.com/user/AMSATUK/videos