Where multiple repeaters are in a chain, as in Reg`s undersea cables,
each repeater can generate its own unique pilot tone. One can check the
tones to determine where the chain is broken.

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How does each repeater generate its unique pilot tone when a trawler or
earthquake breaks the inner conductor. Or do you have another way of
powering repeaters at the bottom of mid-atlantic?

Reg, G4FGQ