DTV Channel Speculation Fest

What’s up with the DTV channel elections announced by the FCC? Not much, considering the electric meters will probably run a few more years at transmitter sites nationwide. However, there are new voids to consider. America hates voids where potential profits lie dormant. Let’s look at the possibilities….

The FCC last month announced one big step toward U.S. TV stations determining their permanent over-the-air digital channels. There were no surprises among San Diego stations, but a few interesting trends here and nationwide.

Most stations on the upper VHF band elected to keep that channel to broadcast DTV. The lower free space loss and terrain forgiving characteristics are just too tempting to give up, at the cost of low signal for viewers who may have equipped themselves with UHF-only antennas. With San Diego viewers, the bowties and Winegard Squareshooter antennas should serve adequately most over-the-air viewers having to receive KFMB channel 8 and KGTV channel 10 from Mt. Soledad.

Many stations, like KUSI, KPBS, and KNSD, have chosen to keep their digital channel and consequently will lose their long-established channel number identity. This saves from having to buy transmission equipment again. It’s also far-sighted because the future branding of stations can’t be tied to channel numbers due to multicasting and independent cable and satellite channel number schemes.

Are We Headed in the Right Direction?

You need only look at the mess of allocations in Southern California to see that we may be missing an opportunity to reorganize the TV bands. In San Diego, for example, over-the-air viewers must aim at four transmitter sites just to pick up signals from the eight most watched English-speaking stations. Spanish and Asian language stations are spread out on even more hilltops. This makes viewing of digital stations so difficult that it’s truly shameful. Even those of us who know transmitter locations and have rotators would never put up with the delay of aiming between sites as we switch channels. And if you have three TVs, should you mount three antenna systems? Homeowners in newer subdivisions are discouraged from installing external antennas at all. And with the current state of RF science, why should they have to? Cellular users certainly don’t mount big antennas with rotators outside.

One of the most profound comments I heard at the NAB Convention this year was when Technology Luncheon keynote speaker, esteemed engineer and author Dr. Robert Lucky proposed that stations cluster in groups of ten adjacent digital channels for a given community. Simple as that. Think of the ramifications: possible sharing of transmission towers and antennas, a single orientation for receive antennas, great opportunities for spectrum reuse, the ability to cluster large numbers of virtual channels for a cable-like experience, and with properly spaced sites, viewers could use simple indoor antennas.

Obviously the number “ten” may have been thrown out for discussion. Los Angeles would probably require more and Yuma might require fewer. What if you could do this with lower power on strategically-located peaks, much like is done in Europe and now rural Utah? In the San Diego region for instance, you could place clusters on Mt. San Antonio in Tijuana, Mt. San Miguel, Mt. Soledad, Mt. Woodson, Palomar Mtn., Santiago Peak, Monument Peak, and so on. Gary Sgrignoli, formerly of Zenith, has been preaching this form of practical digital television. Likewise, the senior men of the translator industry–Kent Parsons of Utah; Byron St. Clair, formerly with Television Technology Corp. (now Larcan); Ellis Feinstein, formerly owner of Scala Antennas–have presented the practicality of this system to the FCC and engineering groups. Others who see only the value of the profit machines of multi-hundred channel cable and satellite systems may ask instead why we bother with over-the-air broadcasting at all.

Would the Last Station to Abandon Low Band Please Turn Off the Filaments?

Low band VHF will be all but dead when the analog transmitters shut down. I count fewer than 35 preliminary choices in that band. Most are rural or medium market stations. Some should know better. Let’s face it, consumers simply refuse to install big VHF antennas in urban and suburban settings now, and rabbit ears pick up too much indoor electrical impulse noise on lower V. The handful of stations electing lower VHF band channels might beg to differ, but can you really keep 30 MHz of spectrum nationwide for a few holdouts?

CBS in Los Angeles and Chicago both had choices between the Devil and the Deep Blue Sea. In Chicago, WBBM bargained for the current NTSC VHF channel 11 allocation of the local PBS affiliate WTTW rather than its old analog channel 2 or digital channel 3. WTTW will probably get to keep their current channel 47 UHF slot–and that eliminates the cost of new transmission facilities–and there’s speculation they got a nice gift from CBS for their troubles. In Los Angeles, KCBS lost its channel 60 digital allocation to the elimination of channels 52 – 69 and chose to take its sister station KCAL’s channel 43 rather than return to channel 2. Some VHF channel affiliates haven’t chosen their final resting channel yet, perhaps working on, or waiting for, on opportunities to trade channels.

What would happen to the lower VHF band after analog shutdown? With the band’s susceptibility to noise and frequent ionospheric propagation, a robust, mobile-friendly digital format with vertical polarization seems a no-brainer. For one possiblility, look no further than the recent Radio World article on progress with Digital Radio Mondaile (DRM). You might know this digital format for its slow adoption on the shortwave bands. According to Scott Fybush, DRM is now being tested in Eastern Europe at 60 MHz and in Japan on the 76-90 MHz FM band—what we consider low band VHF TV. There are problems with DRM with respect to its needing a relatively high signal-to-noise ratio, so the format may need to be modified or dropped in favor of some other. But with some financial incentive to the FCC, this band could become a challenge to the choice of satellite radio with some local content thrown in. Group owners like Clear Channel and Viacom might be interested in fine-toothed format transmissions in the vein of XM Radio. Local organizations might be interested in supplying free-form public service information, traffic, religion, and art music.

It should be interesting watching the border during the analog shutdown. There is no indication that Mexican or Canadian stations will sign off their analog services when the U.S. does. English-speaking over-the-air viewers along the Mexican border will be left with so few choices that such continuation may be of little value. Spanish language border stations will have an incentive to continue to beam to an appreciative over-the-air audience with many active channels.

Of course, it’s easy to get ahead of ourselves with speculation. We’re in the closing months of Round One of a three-round process. The culmination of this work is a DTV Table of Allocations that doesn’t happen till August 2006. Besides, Congress has yet to determine the date of analog TV service shutdown at a time when we continue to see department store shelves full of televisions with analog-only tuners.

June 2005 Meeting – GMS

Global Microwave Systems of Carlsbad demonstrated a remarkable new high definition portable microwave system. With COFDM digital transmission, camera operators walked around the Bay City TV Fox 6 studios, their picture never wavering as a real-time spectrum analysis bobbed and weaved. Presenter Ken Andrew said the new system, which won GMS an AIM award at this year’s NAB Convention, was not ready for network-quality HDTV due to its limited 25 Mbps data rate. But attendees saw a system clearly ready for
news coverage or film-style production monitoring.

One of the most interesting parts of the demo was the active signal
addition circuitry. The processor input IF signals from seven co-linear
vertical 2GHz antennas and output an in-phase addition of all signals,
leading to the best possible reception at all times.

Meanwhile, the chapter seemed to be infused with a new vigor.
Relative to recent meetings, this one was well-attended by a wide
variety of members and guests from all segments of the local
broadcasting population.

New officers were nominated, and will be elected in the coming month
by paper vote of members. Nominations included Eric Schecter of
Jefferson-Pilot Communications for Secretary/Treasurer, Stephen Frick
of KFMB Stations for Program Chair, and Carlyn Yenger of Pacific Radio
Electronics for Vice Chair. The Chair position nomination was tabled
till next meeting.

Society of Broadcast Engineers, San Diego