Sorry to seem ignorant
I thought it was the squawking from transponders - hence I believe I have read people asked to squawk before - I may be wrong.
What happens if that does not work ?
I can appreciate 411A has cut to the chase as to the signalling on final approach - but say your mid destination, ok you want most local airport but you guys would be best to plays devils advocat to worst situation.
I can appreciate you want as early touch down as possible - but should you be far enough out what would you do.
The ATC you cant communicate with as radio down - your near squawking - do you just proceed ?