A red box is what was used to maniuplate pay phones. In short, you would make a call, the operator would ask you to insert the money. You then would play the tone of 25 cents and the call would go through, and you would get a free telephone call. On most pay phones now red boxes don't work, but sometimes you can find one that still works. If you need more info on how these were made or more on how they would work I'd be happy to e-mail it to you. I think its a little too much to post on the BBS here
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