I remember seeing that, If you Zoom in, Its a giant center fed Vertical dipole
with white insulators at the ends...
found this Early web stuff about VT Comms doing it
https://aib.org.uk/vt-communications-launches-pioneering-drm-26mhz-service-in-london/
and these about DRM...
https://www.drm.org/wp-content/uploads/2019/05/ITU-Annex-1.pdf
https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BS.2384-2015-PDF-E.pdf
Rod Watts
Please post or reply to any Radio-related subject / topic or question, all are welcome, Pirate, Legal, Web, Etc.