My two cents.

Digital television is a complicated matter - one need only look at the number of acronyms it has acquired to realize that In Canada and the U.S. digital television is called DTV, in Finland it is DTTV. in the U.K. it is DTT and in Australia and Japan the term is DTTB. In Germany, it is written DVB-T, which stands for Digital Video Broadcasting Terrestrial standard, but it is called digital terrestrial television. And there are related terms to keep in mind.' HDTV (high definition television), ATSC (a U.S. standard) and ABSOC (a Canadian standard).

Since I'm a bit confused about the whole digital thing, I've tried to get answers to 10 questions, limiting the subject to digital TV in the U.S. I hope that these answers are also somewhat enlightening for you. In September, I will call upon Joseph Schatz, vp of the systems integration, software development and consulting company Logica, to expand on these answers.

1) What are the FCC's plans with respect to digital TV?

The FCC has lent each of the country's 1,605 TV stations a second channel at no charge. By Christmas 1998. stations in the 10 largest TV markets will be broadcasting conventional analog (NTSC) signals on their usual channel and digital (ATSC) signals on the second channel The next 10 markets are committed to offering digital TV by the following Christmas. Stations in medium-sized and small markets are required to broadcast digital TV by 2003. Noncommercial stations have until 2004. In 2006 all the analog signals are scheduled to be turned off and the frequencies of the analog channels returned to the FCC to be re-allocated to other users. There is some doubt as to whether the FCC will stick to the 2006 cutoff date because it is unlikely that most of the country's 240 million Tv sets will be replaced by then.

2) Will stations have to broadcast HDTV?

The alternative is to use the new 6 megahertz TV spectrum to broadcast up to five digital channels (in SDTV, or standard definition television) and other services instead of a single HDTV channel.

3) What digital standard will be used?

The standard is called ATSC (Advanced Television Systems Committee). It has a 16:9 aspect ratio with either interlaced or progressed scanning (left to the discretion of the broadcaster) and a 6 megahertz bandwidth. It is important to understand that, while there is one agreed-upon digital transmission standard, there are 18 different digital video options. In addition, satellite and cable TV have digital standards that are different from the digital standard for broadcast TV.

4) Can analog TV sets receive digital TV?

In order to make analog TV sets compatible with digital TV, one will need a converter box, which should cost no more than $300. However, analog sets, which have screens with the current 4:3 aspect ratio, will display digital TV letter-boxed (i.e., with black bands at the top and bottom of the screen).

5) Can digital TV sets receive analog TV signals?

Most TV set manufacturers plan to build two tuners into early digital TV sets so that they can receive both digital TV and analog signals. This will facilitate reception from analog VCRs and DVD (digital video disc) players. Analog programs will be displayed on digital TV sets with black bands on the left and right sides of the screen.

6) Are digital TV and HDTV compatible with direct broadcast satellite systems, cable TV, VCRs and computers?

Direct broadcast satellite systems already broadcast digital TV, but their standards (which vary from system to system - DirecTV and USSB use a digital standard called DSS, and EchoStar uses DVB, a standard popular in Europe) are not compatible with the digital standard for terrestrial broadcast TV A set-top converter will easily solve this problem. However, in order to offer HDTV, satellite operators would have to compress HDTV signals into one 6 megahertz channel, eliminating at least five of their existing channels. At the receiver end, the set-top box that now decompresses the signals into six TV channels would have to instead decompress one HDTV channel However, the satellite operators have not said what their intentions are.

As for cable, the Supreme Court recently required cable companies to carry local channels. The principle transcends the technology, so the ruling also applies to digital or HDTV channels. Once again, a set-top converter will be required to decompress the new signals, be they HDTV or simply digital TV.

As for VCRs, there is a digital VCR standard, which can be received by digital TV sets.

As far as computers are concerned, while the TV industry prefers its interlaced scanning, the computer industry favors its progressive scanning. Both systems can be used. TV set manufacturers will be producing products that will receive both types of scanning. Personal computers already display digital images, and they could be upgraded to broadcast digital TV for roughly $100 per set. Computers will not be able to receive full HDTV, but they will be able to display an enhanced picture (at roughly 700-line progressive scanning).

7) When will digital TV sets be available?

The first digital TV sets are scheduled to go on sale in the U.S. in the summer of 1998. The least expensive sets will probably cost $2, 500 each. These will be "all-formats" sets, capable of receiving analog signals and all of the 18 digital video variations.

8) Will American digital TV sets be compatible with digital TV sets in other areas of the world?

No, but it would be easy for a US. digital TV set manufacturer to come up with sets adaptable to other countries' digital standards. It is only an economic issue.

9) Can digital TV be delivered via conventional telephone lines?

No. The current copper wires cannot carry digital TV. Broadband (e.g., fiberoptic) lines might be able to carry digital TV; however, telephone companies have their own digital standard. Telcos are rebuilding most plants with fiberoptics to the central hub, but HDTV would require fiberoptics to the curb (with coaxial cable to the home) or, ideally; fiberoptics straight into the home.

10) Can digital TV stations offer interactive services?

Only by way of a telephone modem. A wireless (24 gigahertz) interactive system called LMDS (Local Multichannel Distribution Service) is only in the experimental stages. Cable TV will achieve interactivity only with broadband lines.