If you key the mike, does the TX light up? You could go to 121.5 and
use morse code. Clumsy, but possible in a true emergency, so long as
you don't get distracted by it.

No, it didn't. There was no transmit and no receive. I assumed that
when I said "the radios were dead" I didn't need to explain further.

IF the transmit light was going on, and I DID know a bit of morsecode,
it might have been worthwhile to pound out a few letters, but just
barely. What I should have done, as I said, is squawk 7600.