h one for many com- panies to learn. The technology came easily. The business part is still evolving. These companies have traditionally moved slowly. They were a bit slow to get on the bandwagon when the boom hit, but they were even slower to jump off when the meltdown began. Endnotes Even the word "wireless" carries baggage: In the early twentieth century, radio was called "wireless," as in "wireless telegraph," but that term went out of fashion by mid-century, and by the 1970s it was as quaint as a 5-cent bottle of Moxie. It came back into wide- spread use to refer to radio-based telecommunications services such as cellular telephony. Half-duplex means that the station both transmits and receives, but only in one direction at a time, usually on a single frequency. Full-duplex means that it does both at the same time, requiring a pair of frequencies. A typical repeater installation was full duplex at the hub but with half-duplex mobile units, SO a signal at the repeater's input would be retrans- mitted in real time. Narrowband PCS refers to two-way paging service, capable of transmitting short text mes- sages. Although these licenses were auctioned off and systems built, they had a much smaller impact on the marketplace. Specifically, the PCS licenses were allocated by major trading area (MTA), of which there were 51, for the A and B blocks, and basic trading area (BTA), of which there were 493, for the C, D, E, and F blocks. These were based on a Rand McNally atlas and used The Great Telecom Meltdown without permission, a detail that was brought to the FCC's attention somewhat later. Future auctions used U.S. government-defined geographies. Besides its inability to interoperate with 2G CDMA telephones, the bandwidth footprint of UMTS, as originally proposed, was seen as being just a bit too wide to fit into the 5 MHz-wide channels of the American PCS bands. Europeans expected 3G to have its own bands, but the American PCS allocations used up the spectrum originally planned for 3G. See, for instance, "Telecom Y