In the early 1990s, the mobile was a rare luxury.but in recent years it has almost every other gadget as a professional tool, domestic Convenience, and even a fashion accessory. Mobile phone has also shrunk in size. Due to rechargeable batteries which more electricity for longer in a small package.and to smaller, mire efficient electronics that use less electricity. A mobile is basically a low power radio receiver transmitter, plus a tiny microphone to convert sound into electric signals, and. Smaller speaker that does the reverse. When the mobile phone is activated, it send out a radio signal that is answered by nearby mast transmitter -receiver. The phone locks onto the clearest signal and uses this while within range. This range of each transmitter is known as a CELL. The mobile phone continuously moniter the signal strength and switches to alternative transmitter when necessary. The phones liquid crystal display (LCD) shows number, letter, symbols and colour pictures. Newer m
Your Trusted Online Educator for Defence Exams.