Ask any kid from the boomer generation if they’ve ever used two cans and a stretched string to talk with a friend, and you most certainly would hear a resounding yes! A fun plaything that captured the imagination of 1950s children, the rudimentary toy represents much more than a summer afternoon of amusement. The exchange marks how far we’ve come in the ways we communicate, from analog to digital cell phones.
To understand the ingenuity of telephone technology’s growth, we need to take a look back at how this communicative device grew from its early roots. By the time Alexander Graham Bell began experimenting with electrical signals and his ideas about a telephone that would connect people through voice transmission, the telegraph had been the most popular means of communication for transmitting information. Using a dot-and-dash system devised by Samuel F.B. Morse, the electrical telegraph allowed printed material to be transferred through coded signals, connecting North America to Europe and beyond. Bell’s experimentation with the telegraph and electrical signals led him to invent the telephone and the ability to “talk with electricity.”
The telephone’s original system of transmission was based on an analog signal, best represented as a sound wave that continuously fluctuates up or down, gradually increasing or decreasing with each communication. The tin can phone and its use of a taut string along which sound waves move is the perfect example of analog transmission. The main problem with analog transmission is its susceptibility to noise interference, which can lead to signal distortion. This is best understood through the interference displayed on “old-fashioned” devices, heard as static on analog radio and seen as snow on an analog TV screen. With the development of a digital system, voice signals are broken up into a binary code, represented as 1s and 0s, that can transfer data with more accuracy and clarity. Basically, digital technology turns a phone’s original signal into a series of numbers and transmits them to another phone, which then reassembles the numbers into the original data. Digital’s high fidelity, or ability to produce an exact replica of a transmitted signal, further advanced its importance in the market as companies saw the benefits of this new technology. The competition to bring such an efficient and promising device to the world was on.
In April 1973, American Martin Cooper, Motorola engineer who built the first mobile cell phone, met the challenge, making the first public call on his DynaTAC phone to rival engineer Joel Engel at AT&T. From there, cell phones have developed into devices that are “smart,” with internet access, cameras and the ability to monitor a user’s health, finances and everything in between. So, the next time you pick up your cell phone to talk or text or check on your stocks, remember the inventors who changed our connectivity for the better…and the kids talking at the end of two tin cans who imagined the best of life on a sunny afternoon.