Some government research
done a few years ago studied the resistance of various communication devices to EMP (electromagnetic pulse). Although it was aimed at rf energy generated by nuclear events
, the info is applicable to to energy generated during thunderstorm/lightning events
. The gear
included off-the-shelf ham hf transceivers and vhf
Tests showed that the gear
was amazingly resistant to damage when power leads, control leads and antennas were disconnected (per sailfish) from the HF transceivers. Removal
of the wires prevented them from behaving as antennas that fed rf into the gear. VHF
handhelds were found to be resistant even with the antennas installed; VHF frequencies are less vulnerable to the greater EMP energy generated at LF, MF & HF frequencies. Nevertheless, removing them wouldn't be a bad thing.
the same study also evaluated protection with Faraday cages, and found that simple grounded "wire mesh" enclosures were effective; a grounded oven
might protect similarly.
Your idea for a purpose-built cabinet might be practical, coupled with a single-point grounding system, surge protection on the dc/ac wiring
leads, and perhaps protection devices on specific components.
Even with correctly installed lightning/ground systems (which are aimed at protecting people), protection of sensitive solid-state components can't be guaranteed.
Good luck and let us know how your project