it all started with ham radio. then it progressed into the police using a handheld phone radio to the base station. there was a button in the hand set to squeeze for talking.
then as ham radio progressed they made a repeater. located it on top of a mountain the Western Massachusetts. there they set one up for the state police to use. that allowed one policeman to talk over a mountain to base many miles away.
as ham radio progressed it went into hand held units almost as big in some cases as a attache case...mostly battery. and walkie talkies came as the transistors were made into IC chips.
from there as batteries and many more repeaters were made and linked together, ham radio operators could talk across a state using 1 watt of power. some of these repeaters were linked across the whole West coast from Mexico to Canada. and since receivers were made better they could be accessed with 1/10 watt low power. it made batteries last longer.
some hams also made a repeater that was capable of dialing a phone and were talking on their radios long before cell radios were made. but it allowed the police radios handsets from the 1950s to be made into a radio phone service. but everybody had to get a radio operators liscense to use one. very expensive at that. there were only a few channels then and you had to call the operator and have him/her dial your number....."over" as radio communication was only capable of one way talking at a time.
as ham radio progressed some using the newest IC chips made them smaller and more energy efficient added small computers into it. it allowed the to scan digitally several frequencies. eventually several bands not just the ones they were operating on.
voting receivers were developed. it allowed the best receiving repeater to listen and rebroadcast a transmission.
the voting receivers were developed into what is now called a cell site. in a city like NYC several of these sites helped further police talking.
some of the first phones were breif case sized or mounted in cars. but as ham radio progressed so did the minaturization of phones to a single as quoted above brick sized one was made. most of the so called brick was battery.
eventually the size was made smaller each year due to the IC chip being made into almost one chip the samller the less battery was needed to operate it.
soon I understand you will have a cell phone capable of receiving a satellite TV broadcast......coming soon.
hope that fills in the gaps left by brettd.
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