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It means "acknowledgement" in 10code; what response is it?

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Answer: 10-4

10codes are abbreviated radio communication codes. There are many sets of 10codes but almost all of them use 10-4 to indicate "acknowledgement."

Some other example 10codes - drawn from the Savary-Island County Sheriff's office - are: 10-11 (Lunch break) 10-49 (Drunk driver) 10-62 (murder) 10-99 (bomb threat) 10-1199 (lunch break bomb threat) 10-6249 (murdered Drunk Driver) 10-62499911 (murdered drunk driver who made a lunch break bomb threat).


As a former professional marine radio operator (Canadian Coast Guard) I never liked hearing local fishermen using 10-4 to acknowledge radio transmissions; international radio shorthand for message received is 'Roger.'
woodlands at & at &

Check out Carsten Stroud's "Close Pursuit" for a glossary in the back that includes a few other "10" codes, including 10-13 -- "Officer down."
macduff50** at & at &

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