I could have asked this question personally to my respected colleague who gave me a valuable answer to the question, “Is the ‘tame the infinite becoming an idiom or a popular phrase,” which I posted yesterday, but I thought this deserves an independent question.
He, the answerer gave me the comment saying, “(It’s) 10-4. Copy. That’s a good example of how the phrase could be applied, and would be well-understood,” to the question, “Can I say ‘the Palestinian territorial issues is an effort in trying to tame the infinite’, “which I added to the yesterday’s question.
I saw the word “10-4 copy” for the first time. So I searched for its meaning on Google, and found a certain clue from the following text in www.answerbag:
“A lot of the 10 codes are different from city to city and state to state. For example a 10-50 in Indiana is a traffic accident, but in Texas it’s a murder. I personally mix and match; sometimes I say “10-4”, other times I say “clear“.
It seems “10-4” refers to a call sign for something. But what does it represent for? Why “10-4” is combined with “clear”? Can I say “10-4 answer /message/ report/ plan” in describing clear answer /message/ report/ plan”?
Truckers use CB radios to talk to each other during long hauls on the interstate highway system of the United States. Sometimes the chatter is just to pass the time; other times, helpful information is passed between truckers. Truckers have shorthand ways of speaking to each other over the radio, and “10-4” means “Yes, I acknowledge,” similar to the way pilots and air traffic controllers use the term “Roger,” and military radio operators use “Copy.”
In the mid-1970’s, trucker/CB lingo made its way into popular culture, spurred in part by the movie Smokey and the Bandit, and the C.W. McCall radio hit Convoy (which, if you want to hear a whole truckload of CB slang, you can listen to the song on YouTube1).
Even when it was in its heyday, most non-truckers knew very few of the “Ten Codes” (this website lists scores of them), but they did know 10-4, and they also knew the term “Breaker” (which was used to initiate a conversation one of the CB’s 40 channels).
As for the Ten Codes, and why 10-10 means, “I’m done,” and 10-4 means “I heard you,” rather than the other way around, I’m not sure there’s any particular reason. Maybe there is a reason, but that reason is closely guarded 10-35 (confidential information).
According to Wikipedia, CB is still in use today:
CB has lost much of its original appeal due to development of mobile phones, the internet and the Family Radio Service. In addition, CB may have become a victim of its own popularity; with millions of users on a finite number of frequencies during the mid-to-late 1970s and early 1980s, channels often were noisy and communication difficult. This caused a waning of interest among hobbyists.
CB radio is still used by truck drivers, and remains an effective means of obtaining information about road construction, accidents and police radar traps.
1To anyone who listened to the song: by no means do I condone crashing police barricades that are reinforced with National Guard troops at 98 MPH. In other words, don’t try this near home.