A company called Comrex made a 26 MHz. crystal controlled two watt transmitter for IFB until around 2000 or so. Many TV and radio “live“ trucks used them for audio backhaul because they used 26 MHz. which was far removed from the other frequencies in-use by the trucks. With the change in technology to commercial wireless data for remote live video & audio, I doubt anyone is still using their Comrex 26 MHz. gear.I think at least one of them may still be active, but band conditions have been a mixed bag recently. I used to hear a number of these pickup stations during band openings in the 90's. Obviously, these stations were not secure and there was always a risk of a rival hearing a breaking news story and running with it. Satellite made these mostly obsolete, except as a back-up.
Bob
(semi-retired broadcast engineer)