Back to the future

What's a ‘broadcast guy’ doing at a cable show?” Spending several days at the Society of Cable Television Engineers (SCTE) annual expo in Philadelphia gave me the opportunity to ask a lot of questions but the above question was the most common one asked of me. Clearly, there has been a symbiotic relationship between the two industries from day one.

The birth of CATV

The first cable television system is usually recognized as the system built in Astoria, OR, in 1949 by appliance dealer Ed Parsons. Ed wanted to sell television sets but found that a bit challenging because Astoria didn't receive any signals. That's hard to imagine in this era of hundreds upon hundreds of channels to select from over cable, satellite and telco fiber. Back then, off-air was the only option, and there were less than 100 television stations in the United States.

Ed, armed with an FM receiver to tune TV audio, explored the surrounding countryside to find a place where he could receive a signal. When he did, he strung some cable from that spot to his newly sold receivers, thereby giving birth to CATV.

Analog dilemma

The parallels between broadcast and cable have undergone radical change over the years, but some of today's major ones include:

  • We compete for advertising dollars.
  • We share common technologies.
  • We compete for content.
  • We are both transitioning to digital.

For the broadcaster, the transition is mandatory. For the cable operator, it is a matter of survival; it's all about bandwidth reclamation. The cable industry's precious commodity is bandwidth. A 6MHz analog channel can accommodate as many as nine QAM modulated SD digital channels and two or three (depending on QoS levels) HD channels. To compete with satellite providers' 100-plus HD channel offering, and telcos' FTTH and higher high-speed data services, cable needs bandwidth. But therein lies the analog dilemma. One of cable's big advantages is delivering analog signals to the myriad of analog receivers out there, which flies directly in the face of reclaiming analog bandwidth for digital services.

The first part of cable's analog dilemma is the broadcast industry's DTV transition. Despite cable's transition to digital channels and services delivered to digital set-top boxes, there are a significant number of analog-delivered television channels. The average cable home has three-and-a-half television receivers but on average, only slightly more than one digital set-top box. While a small number of those receivers rely on off-air, the majority of sets that are not connected to a digital set-top box are connected directly to cable and view strictly analog-delivered channels.

To prevent nondigital tier subscribers' televisions from going dark in February, cable headends will have to convert those off-air, digital-only DTV signals back to analog! So, the broadcaster — after taking painstaking care and spending millions of dollars to deliver pristine digital signals — will find the majority of cable viewers still viewing an analog signal.

Then there's the nightmare scenario: SD content upconverted to HD by the broadcaster and transmitted digitally only to be received at a cable headend where it is downsampled to 4:3, converted to analog and then sent through several miles of cable trunk and distribution amplifiers before appearing on the subscriber's receiver. Any resemblance to original content is purely coincidental!

Recent statistics released by the NTIA indicate that consumers have applied for DTV converter box coupons in record numbers. The coupons, which expire 90 days after being issued, however, have also been expiring in record numbers.

According to the NTIA, 58 percent of all issued coupons expire unused. With factors such as this added to continuing consumer confusion, the cable industry expects that a large number of analog viewers will be driven to hook up to cable's analog spigots as February looms closer.

The second part of cable's analog dilemma goes back to the bandwidth issue. To efficiently maximize all available bandwidth, ideally cable doesn't want to dedicate any of its bandwidth to analog signals.

Enter the digital-to-analog (DTA) converter. Cable equipment manufacturers have started demonstrating prototypes of tiny, inexpensive DTA converters that accept a stream of digital channels from the cable plant and convert them to analog for tuning and display on a subscriber's receiver. Deployment of such devices would enable a cable operator to fully convert the entire plant and distribution system to its highest form of bandwidth monetization — digital-only streams.

The broadcaster can only hope that cable gets it right. Whether at the headend or in the subscribers' home via a DTA device, conversions not only need to address program content quality but also a host of issues ranging from closed captioning to content advisories. Welcome to the analog transition.

Anthony R. Gargano is a consultant and former industry executive.

Send questions and comments to: anthony.gargano@penton.com