Dave, KI4PSR gave the Technical talk at the February Monthly Meeting with the first in a series of presentations on antenna tuners.

In this first installment Dave covered the basics of antenna tuners and dispelled some myths (a tuner does not improve the radiation efficieny of the antenna.) An overview of reactance concepts, reactive matching and an introduction to L-network tuner configurations were next followed up with a brief demonstration.

Dave says this presentation was inspired by the work of Davide, IZ2UUF

https://www.iz2uuf.net/wp/index.php/2019/03/22/how-does-a-tuner-tune/

and provided a link to one of IZ2UUF’s youtube videos on tuner losses:

https://www.youtube.com/watch?v=mmVMQbXmaHA .

Dave’s presentation is here:

https://wcares.org/wp-content/uploads/2020/02/KI4PSR_HOW_DOES_AN_ANTENNA_TUNER_WORK.pdf

along with pictures of his demonstration setup: