From the BAA Members page-
David wrote a book entitled Setting-up a Small Observatory, in Patrick Moore's Practical Astronomy Series (Springer). He often contributes to Astronomy Now magazine. he gives talks, mostly around practical amateur astronomy, but also sometimes on historical and cosmological subjects.
David is currently (2018) on the Board of Trustees and Council of the BAA. In June 2018 Council appointed him the first Director of the new Equipment & Techniques Section of the BAA (a successor to earlier sections concerned with telescope-making and the like). He is also on the committees of the Jupiter and Mercury & Venus Sections and Chair of the Sir Patrick Moore Prize committee. David is also a Vice-President of, and Publicity Officer for, the West of London Astronomical Society.

Date	Talk at GAS meeting
1 Mar 2012	High-resolution Imaging The Bright Planets
4 Apr 2019	Lunar Imaging
4 Mar 2021	A Zoom Talk: The History of the Telescope