==Phrack Inc.== Volume One, Issue Six, Phile #6 of 13 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Cellular Telephones [Written By The High Evolutionary] =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= I assume that most of us know many of the technical aspects of Cellular Phreaking therefore this file is intended for general information as to how these unique devices operate. -------------------------------------------------------------- Cellular is likely to be successful because it provides dramatic improvements over the historic automobile phones. For years, mobile radio-telephone service was an extremely limited proposition. There were only forty-four radio channels available, and a maximum of about thirty were assigned to any one area. That meant if all thirty channels were occupied-one conversation per channel-and you were the thirty-first mobile phone user who wished to make a call, you would have to wait thirty minutes or more, even in a city the size of New York. As you can imagine, mobile radio-telephone service like that could not become very popular. Even with the limited number of channels, long delays in making calls during busy periods, and often poor quality transmission, there were big waiting lists for mobile service. But with a fully equipped cellular radio-telephone system, it is possible to make 5000 times as many calls simultaneously in the same metropolitan area, opening up the service to anyone that can pay the hefty prices. That is because cellular radio-telephones systems are technically quite different from traditional mobile telephones. First, the FCC (Federal Communications Commission) has allocated far more channels to cellular, 666 in all. Second, those 666 channels are broadcast from many different locations. In the old mobile telephone systems, there was one powerful radio station with a large antenna that served an entire city. In the new system, a geographical area is honeycombed with many cells, hence the name 'Cellular'. Each cell has its own low-powered radio transmitter and receiver. As a car with a cellular telephone or a person carrying a portable moves from one cell to the next, the call is transferred automatically. You're unlikely to notice when this transfer takes place, even though your phone is suddenly switched to a different radio station and to another channel while you are talking. Because the cellular signal is low-powered, it doesn't go very far. This permits the same channel you are talking on to be used for calls in other parts of the same metropolitan area without interference. This would mean cellular radio-telephone systems can serve a very large number of customers in an area because there are more channels than before-and the larger number of channels are reused. Unlike local telephone service, which is provided by a monopoly, there is competition in cellular. Two classes of companies are allowed to offer cellular telephone service in every market. One cellular system can be owned by a telephone company, the other by someone else. The two-company rule was adopted by the FCC so that AT&T, which developed cellular, could not monopolize the whole thing. Cellular Telephones come in two basic versions, as car phones and portable phones, with a briefcase hybrid. Car phones are by far the most common, because they are much cheaper. But most believe that, ultimately, portables will be the most popular. Washington Post Company president Richard Simmons, whose company is a partner in several cellular systems, even predicts that by the early 1990's "There will be phones roughly the size of a calculators that you carry around in your pocket. They will cost no more than five hundred dollars. They will emancipate people from the necessity of locating a phone to make calls. The bad news is, you will never be able to get away from the phone, and we'll call it progress." Car telephones include a small transmitter-receiver unit that is usually mounted in the trunk, an antenna and a control head that includes the handset. In most cellular systems, the telephone touchpad is located on the handset. Many domestic and foreign manufacturers make cellular car phones, but so far only Motorola makes portables, the DYNA T-A-C 8000X and 8000S. Motorola's portables look like a slightly enlarged, somewhat chunky telephone handset, with a stubby antenna at one end. Portables are less powerful than car units, so they can't be used with some cellular systems. The portable's other limitation is battery life. A portable can listen for calls for about eight hours, but it can only transmit for only thirty minutes. After that time it must be charged for a minimum of an hour. The following American cities have cellular telephone service or soon will get it: New York Denver Los Angeles Seattle Chicago Milwaukee Philadelphia Tampa Detroit Cincinnati Boston Kansas City San Francisco Buffalo Washington Phoenix Dallas San Jose Houston Indianapolis St. Louis New Orleans Miami Portland Pittsburgh Cleveland San Diego Atlanta Baltimore Minneapolis -------------------------------------------------------------- hip of Metal Downloaded From P-80 International Information Systems 304-744-2253 12yrs+