I've been adding webinars by PracticalShowTech, mostly they involve RF- mics, IEMs, point
, intercom; COMS (in caps) of the matrix and wireless types, including CrewCom; RF over fiber (cool stuff).
The folks behind PST are Mac
Kerr (moderator of Live Audio Board), Pete Erskine of Best Audio (when all the other old road
dogs have gray hair, Pete went green!), Henry Cohen of Radio Aktiv Designs (wireless coms) and a rotating cast of Greek Chorus. Serious CVs....
All the webinars have been archived on either GoToWebinar or Zoom
(depending on original streaming). The archive page
Free, but you have to sign up each time you view. The content is well worth the minor inconvenience. Take a look!