"Richard Harrison" wrote
The Faraday screen is common in radio stations. It was put there not to
affect the antenna match but only to eliminate capacitive coupling to
the antenna. It also serves as a path to earth for many antenna
lightning strikes as evidenced by numerous pits and metal hrom them
splashed about the enclosure.
______________

This must be a very dated observation. In my experience, and as confirmed
to me this morning by colleagues and consultants who design such networks,
MW broadcast Antenna Coupling Units commonly do not contain Faraday screens.

Lightning protection for most MW broadcast antenna systems is provided by
some combination of a small inductance in series with the tower feed (copper
tubing with a helical loop or two in it to connect the ACU output to the
tower feedpoint), an arc gap across the tower base to ground adjusted to
flash over at the lowest practical peak voltage, and a static drain choke
(path with high Z for RF, but low DC resistance to ground).

RF