75 years later, over the air television continues to evolve
The below post is written on behalf of AddonHQ by Samuel Cook, a freelance writer with a special love for technology and gaming. If it can be researched, he can (and probably will) write about it.
Most of us have fond -- or frustrating -- childhood memories involving television. The TV has been a focal point in households since it first became a viable source of entertainment. Adoption of the television in the U.S. was slow at first, but by the end of the 1960s, there was nearly one in every home. Yet owning a TV often meant accepting a couple of unavoidable facts about the technology. First was that you couldn't watch what you wanted when you wanted or even where you wanted.
Television watchers at the time were bound by a schedule, not of their own choosing. Multiple channels existed, increasing in number every year, but there was no such thing as on-demand. Secondly, (and this mostly applies to the more mainstream adoption of cable by the 1990s) most users had to accept the almost endless fight with the "rabbit ears" antennae, moving them this way and that to get them in just the right position for a clear-ish signal. For most people, and through most of television’s history, that antennae and the over-the-air radio signals they received were an essential part of television watching.
OTA: A History of Firsts
Over-the-air television, or OTA, was indeed the first type of television. The original OTA TVs worked via an analog signal that transmitted both audio and visual information. Those bunny ears that so many people fiddled with endlessly, known as a dipole antenna, received those signals. Once the ultra-high frequency (UHF) or very high frequency (VHF) signals hit the TV, they were translated into the images we enjoyed. That meant all of the “I Love Lucy”, “Jetsons” and “Family Matters” one could hope to watch. At least, that was only while those shows were broadcasting, and only if your antenna was good enough to properly receive the signal.
Therein was the major problem with OTA TV. One’s television enjoyment was severely limited by the various television networks’ own schedules. ABC, CBS, and NBC, all of which originally ruled the radio airwaves, now ruled television. Yet because the original analog signals running on the UHF and VHF bands were still radio signals, they were still susceptible to all of the weaknesses and failings of traditional radio signals. That meant interference from other television signals on the same or a similar frequency, or an inability to get around mountains, buildings and occasionally tall trees. Even a rough storm could knock out the signal. Not because of a downed power line or a loss of electricity, but because of the electromagnetic activity seeping through the air.
The Broadcasting Advantage? Free Access
However, OTA TV has always had one distinct advantage: it’s free. The only cost associated with this form of television is the equipment. While OTA TV was the most common way to access television, falling prices and cheaper equipment meant almost anyone could afford the cost of a television set and an antenna. Although radios were still as popular as ever, the ability to actually see culturally and historically significant stories have a much deeper, long lasting impact. And no one wanted to be fooled by another "War of the Worlds" incident.
Indeed, broadcast TV was, in many ways, one of the most influential technologies of the 20th century. Through the now-antiquated technology, society watched as Martin Luther King Jr. gave a powerful speech that fundamentally changed a nation at its core. As Neil Armstrong took his first, fateful step on the moon, some 238,000 miles away. As John F. Kennedy was assassinated while sitting next to his beloved wife. As Richard Nixon waved once more before flying off in a helicopter in disgrace. As parts of Los Angeles burned to the ground in riots that sent ripples throughout the modern world.
Analogue TV Fades, Digital TV Rises
Analog OTA TV has been with modern society for its greatest achievements and its most heartbreaking defeats. But it was also a technology that was too flawed and too imperfect to last. Digital OTA TV tuners began to replace the original rabbit ears by the 1990s. And by 2009, the Federal Communications Commission had dictated that every analog signal is officially cut off for good. Digital technology transformed all other forms of technology, and television was no exception. DTV is the current standard, yet even still is much older than most people realize, with more untapped potential than most other mediums.
Around the same time cable television began to take off in the 1980s, digital television signals were in early development. In 1990, technology company General Instrument proved a television utilizing digital signals was a feasible idea. This breakthrough was so worthwhile, in fact, that the FCC halted a decision on accepting a new analog standard in favor of seeing how the new digital technology would play out. The end result was the passing of the Digital Transition and Public Safety Act of 2005, a law which effectively put a death date on analog television.
There were good reasons for the FCC to make such a dramatic move toward digital. Digital TVs work differently than their analog-based predecessors. Where analog signals are wholly based on radio waves, albeit broadcast in higher frequencies, digital signals interpret a sampling of analog signals to convert them into electrical signals. Digital signals are also unaffected by the environmental influences of analog. The only thing that potentially impacts the signal quality is the distance. When a digital signal does not reach far enough, the receiver simply cannot convert the images and video, revealing nothing on the television.
DTV Gives Rise to New Tech
Over-the-air digital television helped give rise to a host of new television technologies that would otherwise have been impossible or unnecessary. Digital receivers do not need the iconic “rabbit ears” to work. The location of the digital receiver ultimately does not matter as well. Therefore, that long-standing feature of traditional analog TVs was soon dropped. The shape and size of a DTV tuner also do not matter nearly as much, allowing for miniaturization of the receiver and a much cleaner, less tangled look while watching television.
DTV has afforded many new companies the opportunity to explore the technology, creating new and interesting antenna designs to service the industry. The Mohu Leaf antenna is a good example of this. The paper-thin design completely throws the traditional antenna design on its head. The antenna is amplified (requiring its own power source), helping to compensate for the line-of-sight limitation on digital signals. Mohu and other companies are championing this flat antenna design. Alternatively, a host of interesting external antennas exists that can capture digital signals that come in unequivocally clearer than what's possible with either cable or satellite.
Perhaps on the more wonkish side of things, DTV has also led to many DIY antenna projects. This includes the heavily math-based fractal antenna, which, as one might guess by the name, uses the mathematical phenomenon found in fractals to create an efficient means of capturing digital signals. Perhaps one of the most important things about DTV is the manner in which is inspires individuals to experiment with the technology in new and interesting ways. In a sense, digital terrestrial television gives more power to individuals and small start-ups to test the waters in ways that would have been impossible with analog.
We can see this through the creation of other new DTV technology as well, such as a new generation of digital, over-the-air DVRs. Because all over-the-air signals are now digital, this opens up the possibility to relay those digital signals through an internet connection. Devices such as the Tablo DVR do just that, allowing you to watch OTA DTV channels on any television without the need of an antenna attached to each TV. This is a technology that would have been fundamentally impossible with an analog signal, but that is now possible, and with greater depth, with digital signals.
Interestingly, both of these technologies are increasingly combined to create an over-the-air TV experience with on-demand options. TiVo, which has long been a DVR industry leader, now has an OTA DVR that also functions as an on-demand streaming device. Their Roamio can connect to popular on-demand streaming services, as well as record and play OTA DVR shows. The integration of digital signals and internet functionality only increases the potential uses of over-the-air digital television and the devices created to both capture and play those signals.
Unexpected Advantages, Uncertain Futures
Because digital signals also transmit much more data, high definition transmissions are simply easier and better that with original OTA methods. Whereas HDTV was once only possible with cable or satellite television, now high definition signals are not only possible on digital terrestrial television, but are in many cases are now standard for DTV broadcasts. Most new DTV antennas are also capable of capturing and playing back 4K television signals, with a promise in the future of this upping to a potential for 8K reception.
Analog signals were the standard for over half a decade. Yet fast forward to 2016. When was the last time you saw a dipole antenna? Bent and broken in the back of a dusty thrift store? Shoved away in the dark corners of your grandparents’ or great-grandparents’ house? A museum? As of 2009, that antenna, at one point the only real way to even watch television, effectively became extinct in the U.S. Digital over-the-air signals replaced the analog signal, much to the chagrin of some, but with an overall benefit to television viewers overall. Nevertheless, over-the-air television has a bit of an uncertain future. The Federal Communication Commission is in the midst of selling off much of the bandwidth utilized by OTA broadcasters, effectively cutting off some growth in this area. However, new signal standards may help revitalize DTV in ways not seen since the analog television was first popularized.
The ASTC and the Digital Standard
The governing body for DTV is known as the Advanced Television Systems Committee (ATSC). This governing standard replaced the original National TSC standard that came before it. ATSC is responsible for the first DTV standard set in place in 1996. This allowed for the first digital transmissions, receivable only through a digital tuner. At the time, many analog TV sets did not have the capability of accepting DTV signals. There was no backward compatibility, and many TVs could not even process the digital signals anyway.
In recent years, the ATSC, along with broadcasters, developed new technology that now allows over-the-air broadcasts to be stored for later on-demand viewing with devices such as those from Tablo or TiVo. Known as ATSC 2.0, DTV users can now use a variety of DTV digital video recording devices to not only watching HDTV broadcasts over-the-air for free but store those broadcasts with a digital video recorder (DVR). With the advent of ATSC 2.0, OTA TV has essentially caught up with cable and satellite television in what it can do. The ability to interact with internet protocols also provides DTV with a unique advantage, especially over analog signals. That means a television set or DTV box with a wired or wireless receiver can interact with the digital signal for a greater increase in services and accessibility, including more on-demand options and programming guides. ATSC 2.0, however, is now considered a mere stepping stone for something even greater.
Mobility is Coming to OTA
In the future, the ATSC plans on developing what is known as ATSC 3.0. This new iteration of digital terrestrial television will take OTA broadcasting away from just the television and place it right on your mobile device. As it stands, even with ATSC 2.0, signals still require a receiver that must be much bigger than a mobile device. However, ATSC 3.0 comes with the promise of a signal that can be processed through a receiver small enough to fit inside a mobile device. This promise also comes with full integration with internet protocols. ATSC 3.0 opens up a new world for OTA broadcasting, where users are no longer tied to an immobile television. This has been one of the primary reasons OTA TV has failed to keep up with other entertainment media.
In an open letter, ATSC Chairman Rich Chernock wrote, “Today, people want the capability to watch nearly anything they want, on any device, wherever they are—with content delivered over the air, over cable or satellite, via the Internet or locally stored. It is clear that the broadcast industry must evolve to accommodate this desire.” Broadcast television has always been about access. Original terrestrial television opened up access to the outside world. Digital television helped bring that access in much clearer, more easily accessible way. But broadcast television, at least for a time, experienced an almost unavoidable decline. However, new technologies and changes in digital standards may help make broadcast TV not only relevant again, but more importantly, help revitalize the free access to information that was the hallmark of OTA TV.