Even though the telephone was the first device that was widely used to employ digital (pulse width modulation) electronics, most of us cut our digital teeth on the personal computer. The digital nature of the phone system was invisible to us until the advent of cellular smart phones. The digital portion of the telephone (and co resident internet) system started at the telephone company office. Digital made sense to the electrical engineers. It was a lot easier to create a circuit that was either on or off. We all grew up with the light switch. Our lack of exposure to digital devices was a portion of the trepidation that we experienced every time we added a new digital device or card to the data streams within our computers. Usually this trepidation was well founded in that frequent system crashes occurred as we tried to activate yet one more device. Most of our computers were regularly sent to the computer repair shop to sort out the dueling digital streams.
It is not surprising that we think personal computer when the discussion topic of digital is brought up. Yes, the personal computer is still digital. What has crept up on us is that virtually every electrical device that we use is now digital. Even the humble electric light
that was the impedes for deploying our electric grids has evolved into a digitally driven LED (Light Emitting Diode) array. Most people are unaware that digital circuits pulse the LED’s to achieve the brightness without burning them out. The pulse circuits are powered by digital converters that create the proper voltage. Each digital step creates its own digital stream.
Most of the digital devices that we buy have been tested. Like the medications that we employ, this testing is done in isolation. We all hope that we will only need one medication at a time because next to no testing has been done to determine whether medications will work in combination. Vehicles have many electric devices. Each device runs on its own set of digital streams. All of these devises share a common wiring system which opens the door for dueling digital streams. Unlike the medical community, most vehicles devices are tested to confirm that they can work properly together. This does not totally prevent unauthorized engineering changes from creating dueling digital streams. I am currently recovering from an event where the digital stream from the headlights shut down the vehicle control.