Once upon a time, like 35 or so years ago, there was a loophole in the FCC rules meant to permit manufacture and sale of transmitting equipment that doesn't meet the FCC limits for legal use in the USA. Think Motorola, Harris and such making radios for the Saudi armed forces, for example. This exemption applied only to merchandise that was manufactured to be sent outside the USA, where it would not be used in a way that violates the limits the FCC places on legal transmitters, like a 40-channel CB. FCC rules apply only in the USA and colonies, er, "possessions".
Hence the term "export" radio. In the 1980s, bootleg radios that exceeded FCC limits for CB use would appear with a label "for export only" stuck to the carton. Sellers in Canada would ship bootleg radios to a USA customer, since no such regulation applied to them. A French company "Dirland" was using this method. Other sellers would drop-ship a radio from a warehouse in Guatemala, with a sticker on the carton that said "farm equipment". Similar tricks were used to disguise sale and shipment of linear amplifiers. The Dirland radios had a tiny slide switch inside that would activate the CB coverage. These days you usually need a soldering iron to "un-cripple" the radio.
This ruse kept up for a while, and the market grew. Demand rose, and wholesale companies got bolder. Bootleg radios would get smuggled into the country by the container load. Eventually the owner of Ranger Communications International got arrested at his hotel room in Vegas in the mid-90s for importing "illegal" radios. The judge threw out the charges and apologized before cutting him loose. Right about that time, some genius figured out that if you simply crippled a radio at the factory so that only 10-meter ham frequencies would come out of it when you key the mike, you could get a radio past any customs check, no problem. Of course, the FCC responded with a list of "dual use" radios that they said you were not allowed to sell, but the camel's nose was in the tent and no rule to prevent them from coming over the border.
Uniden had already done more or less the same thing around 1990 when they introduced the HR2510. It would only tune the 10-meter ham band. Until you jiggered two pins on the radio's CPU. This unlocked frequencies from 26 to 28 MHz, and a whole separate "band" with the USA 40 CB channels in the proper order. That part of the chip's programming didn't just appear from nowhere. Uniden put it in there when the chip's program was written. Made the 2510 a much bigger seller than it would have been with only 10 meters in it.
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