Most Americans get their TV (NTSC or ATSC) from their local cable company something on the order of two-thirds of all households subscribe to cable-TV services. Cable companies (generally referred to as MSOs or multiple-system operators, as most cable companies own and operate cable systems in dozens or hundreds of different cities) have been extremely aggressive over the past ten years, rolling out new services like digital cable, cable modems, voice services (cable telephony), and Video on Demand (VoD).

Cable companies have, however, taken their sweet time in the HDTV realm many cable companies decided to drag their feet (for various technical and business reasons) when it came to offering HDTV to their customers. Luckily, the threat of HDTV from satellite combined with technical advances and some regulatory agreements has given cable TV providers a big burst of HDTV energy. Now we’re even seeing ads from our local cable companies bragging about how they have more local HDTV than any satellite company. In this article, we give you the basics on how to get HDTV from your cable company, and what to expect when you do. We also tell you about some of the other services you can get from your cable company (things like digital cable, which are actually the majority of channels available on your HDTV, even though they aren’t HDTV themselves). Finally, we talk about an exciting new trend a new system of TVs and “smart cards” that let you forgo the cable box and plug directly into the cable coming out of your wall. High-Definition Cable The crème de la crème of cable services is HDTV over cable, and it’s nearly everywhere. Cable companies are now offering HDTV services in 83 of the 100 largest markets in the U.S., according to the National Cable & Telecommunications Association, or NCTA (www.ncta.com), the largest industry group of cable operators. Getting on the QAM bandwagon The biggest difference between HDTV signals on a cable system and those broadcast over the air (see Article 8) revolves around the system used to modulate an HDTV signal for transmission as radio-frequency signals across the cable system. Broadcast HDTV uses a system called 8-VSB (vestigial sideband), while cable usually uses a system called QAM (quadrature amplitude modulation). What’s the difference? Well the technical specs are for the engineers what’s important to HDTV viewers is that you need a different kind of HDTV tuner to receive QAM signals than you do to receive 8-VSB (though many newer TVs are now including a tuner that can tune into both types of signals). For most people, HDTV cable service will come through an HDTV set-top box (or cable box) that has a built-in QAM tuner. Encrypting and decrypting The other big difference between broadcast and cable HDTV concerns encryption and “premium” cable channels. Broadcast HDTV channels over-the-air broadcasts that you pick up with an antenna are free for the picking (up). If you receive the channel, you can watch it. Many cable TV HDTV channels, on the other hand, are considered premium or for-pay content you have to pay extra every month to receive them. Because of this arrangement, most cable systems use an encryption system that scrambles the signal (using an encryption algorithm or formula). This means that even if you have a QAM tuner (whether built into your HDTV or attached to it), you won’t be able to watch these programs without some hardware to decode the encryption (in English translated from Geekese, that’s unscramble the picture).

In some cable systems, the local broadcast HDTV channels are transmitted across the cable system unencrypted if you have the appropriate tuner, you can view these channels without some sort of extra decryption hardware. While a very big exception to this rule is starting to hit the market, the current situation for most cable HDTV viewers is this: You need a set-top box from your cable company to view HDTV. This set-top box handles the QAM tuner duty, connects to your cable company to authorize you as a paying customer, and does the decryption and unscrambling of any premium channels. Pricing for HDTV set-top boxes varies widely by cable company. Some may charge you a monthly rental for the set-top box, but nothing for your HDTV channels. Others may not charge for the box rental, but then charge you on a per-channel or package basis for HDTV channels others may have a combination of these two approaches. In many cases, you’re required to get the digital-cable packages in order to get HDTV channels beyond ABC, CBS and NBC. (Frankly, it’s a mystery to us what your cable company offers, pricewise, so check out its Web site.) Your HDTV cable box will typically also control and enable all the cool (but non-HDTV) digital cable functions that you’ll want to use on your HDTV things like VoD and on-screen program guides. We are writing this just as a midsummer 2004 deadline is looming that requires cable companies to provide services to customers without a set-top box. See the section at the end of this article titled “Going Boxless” for more details on this new development. Digital Cable The next notch down (picturewise) from cable HDTV is digital

cable. This name has been the source of almost boundless confusion among many smart people we know simply because the whole “digital” thing gets people to thinking of DTV and once you have DTV in your head, well then, HDTV follows. So let’s get this out of the way right away. Repeat after us: “Digital cable is NOT HDTV, digital cable is NOT HDTV . . .” Defining digital There, we got it out of our systems (and hopefully yours). Now, we should hasten to add that in some places, HDTV channels may be part of (or an optional component of) a digital-cable “package.” But that’s just marketing. Digital cable itself means two things:

-  Digital transmission and compression: Standard-definition NTSC analog-TV channels are put through a digital wringer and come out the far end as digital channels (MPEG-2, typically, if you care to know the tech stuff) that take up less space on the cable system (in other words, you can cram more of them onto the cable system, so you can get the mythical 500 channels). These digital channels are then digitally transmitted using a QAM system.

-  Two-way communications: Digital cable utilizes two-way communications over the cable system (the set-top box can send data “upstream” from your home to the cable office). Such two way communication allows more sophisticated services like VoD to work and that’s why most cable companies began offering both digital cable and cable modems (which use the same upstream infrastructure) at around the same time. Getting the benefits So what does digital cable offer you (and your HDTV)? A lot actually (though, to repeat ourselves, HDTV isn’t part of what’s offered):

-  More channels: Compressing each channel digitally allows more channels to be sent to your HDTV.

-  A high-quality NTSC picture: Because channels are transmitted digitally, they are less prone to suffer from interference and “noise” than analog cable.

-  High-quality audio: Stereo audio is provided with most programs; some channels may include a Dolby digital surroundsound audio stream.

-  An on-screen program guide: Most cable systems include an interactive program guide that lets you view a week or so’s worth of shows, view details about each program, and set up reminders and timers for recording.

-  Access to Pay per view: Unlike old fashioned pay per view (PPV) programming, you don’t need to call the cable company to watch a show (like a movie or sporting event) you can simply press a button on your remote to order.

-  Access to VoD: The flagship service in any digital cable package is video on demand. This service uses the two-way network and on-screen guide, and allows you to select any movie or program from a library of programs retained on a server in the cable company’s network when you hit Play on your remote, the program begins streaming down to your set-top box. You can pause, fast-forward, and rewind, just as you can with a DVD. Getting the digital box Today (though this will change very soon), you need a digital-cable set-top box in order to take advantage of all these neat digital-cable services. If you have an HDTV set-top box from your cable company, you probably already have a box that can take advantage of digital cable. (There are usually only a few HDTV channels on any cable system; it makes no sense to build a box for HDTV alone.) Like the HDTV-specific set-top boxes, digital cable set-top boxes are rented or leased to you (the customer) in a variety of different ways such as a monthly box lease, a monthly service fee, or a combination of those. Look for set-top boxes that have extra features for example, Pat is currently using a set-top box from Scientific Atlanta that supports HDTV and digital cable, and has a built-in DVR (digital video recorder see Article 12 for more info).s Analog Cable The easiest cable signals to tune into are analog cable channels.

Depending upon your cable system, all, none, or some of your cable channels will be analog (the latter case occurs when the first 50 or so channels on your system are analog, and all higher channels are digital). Analog cable is nothing more (or less) than NTSC, analog, standard- definition TV programming sent over cables instead of the airwaves. With the vast majority of HDTVs (that is, any HDTV that is not just a monitor, and has an NTSC tuner built-in), you can view analog-cable programming by simply plugging your cable feed (the RG6 cable and F-connector see Article 3 for more details on these cables) into the back of your TV. If you’re receiving digital cable or HDTV from your cable provider and are using a set-top box, you don’t need to do anything special to tune into the analog channels. Your set-top box will automatically tune them in and send them to your TV. Some plasma TVs (Article 23) and most front-projection TV systems (Article 22) don’t have a built-in NTSC tuner. If you’re not using a set-top box, you can always use the NTSC tuner built into your VCR (VHS, S-VHS, and D-VHS VCRs all have NTSC tuners builtin) as your NTSC tuner. Going Boxless Like many other electronic devices and services, digital cable (and HDTV cable) is going plug-and-play. With the help of the government and industry organizations (such as the Consumer Electronics Association), cable TV providers have gotten together with technology vendors (TV manufacturers and the folks who build the infrastructure components of a cable network) to come up with a system that lets customers kick the cable box to the curb! As we write this, the first iterations of this “boxless” digital-cable system are beginning to be announced and trickle onto the market. We haven’t been able to test them out. We’re sure they work, and work well, but sometimes such transitions take longer than expected so don’t be surprised if it’s a few years before this becomes commonplace. So what’s going on? Two main things are happening:

-  TVs are being built as digital-cable-ready (DCR) just as regular analog TVs have been built as cable-ready for analog cable for years. These TVs have a QAM tuner built-in, and also have a slot for a “smart card” called the CableCARD.

-  Cable companies are getting ready to rent these CableCARDs to their customers. A customer with a CableCARD and a DCR HDTV can simply plug the CableCARD into the HDTV the card basically gives your TV “permission” to unscramble encrypted premium channels. This permission-giving process is called conditional access in the cable business. No, we won’t test you on that. Just thought we’d share. With this DCR HDTV and the CableCARD, you simply plug the cable into the back of your TV and you’re ready to go. The first generation of CableCARD devices will be one-way only so they will let you watch premium channels, but won’t be able to communicate back “upstream” to the cable company. This means that the initial CableCARD deployments won’t support digital cable services such as program guides, pay per view, or VoD. Eventually, an updated, two-way CableCARD will become available, allowing DCR HDTVs to access more of these advanced digital-cable features. Cable companies hate paying for expensive set-top boxes, but they also like the concept of having a piece of gear in your home that controls much of your TV viewing (and maybe even your Internet surfing and phone calls, too!) so don’t be surprised to see your cable company still pushing set-top boxes your way, even long after CableCARD hits the streets.