[gcruse]

In 1961, I was a young sailor going
to radio school on the Norfolk naval base.
We were learning to receive and transcribe
Morse code at maybe 20wpm at that
phase of the training.

One Saturday, they ran an old Flash Gordon
serial episode at the exchange.  Flash was
using, and I'll never forget it, what he
called a 'skillioscope' (your spelling may vary).
The skillioscope was putting out code at
at about a dit or a dah per second.  But
Flash was reading information out of it
as fast as he could talk.  Naturally, a
movie audience composed of probably
twenty-percent radioman cracked up
long and loud.  It was a hoot.

[Erasmus]

I don't have any examples at hand, but lots of the technicians in the movie industry were (and are) hams.

So when the techs were asked to come up with some 'morse code' effects, they could be counted on to embed some hidden message--often a snippet of a QSO with their own call signs.

I know there are some examples in the Disney oeuvre.

Here's a link I found.

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