After years of study and debate, cable television is about to become a reality in Fairfax County. Over the next 3 1/2 years, Media General Cable will be stringing cable lines from one end of the county to the other. The first homes will receive service within a few months.

In anticipation of that event, last week Washington Post staff writer Sandra Sugawara interviewed Sam A. Jernigan, president of Media General, and put to him the most commonly asked questions about the system.

A detailed county map -- by Washington post staff artist Dave Cook -- showing those first-phase areas scheduled to receive cable service by March 1984 appears on page 7 of The Weekly.

The following is an edited transcript of the interview:

Question: When will cable service be available in the various neighborhoods?

Jernigan: Well, a lot will depend on which year [your neighborhood is scheduled to receive cable]. We have a three-and-a-half year construction growth scheduled. And we have maps available that, when you call into our office, you tell us what street you are located on, we can pretty much tell you which one of the years you will be in.

Q: What are the hours for that hot line?

Jernigan: It's the normal business hours on Monday through Thursday, 8 a.m. to 6:30 p.m. On Friday, it's from 8 a.m. to 8 p.m. And on Saturday it's from 10 a.m. to 4 p.m.

Q: What is the phone number?

Jernigan: 378-8400.

Q: Is it possible to get cable before you actually bring service into a neighborhood?

Jernigan: We have available an interim service for town houses, condominiums and apartment locations where there are more than 200 units. It is called our early bird satellite system. And what we do is we go in and we install a satellite receiving dish and then we bring to those multidwelling locations two satellite signals. . . . We only give to them satellite signals. The [continue to receive] the signals that they currently receive [over the] matter antenna system in the building. We just give them an optional satellite signal service.

Q: Can the individual without cable service buy and use a satellite dish, or is that against the law?

Jernigan: They are available, but they're quite expensive. . . . I really don't think the expense is worth it. Additionally, and probably most people have read . . . that Home Box Office, which is the leading pay-TV supplier, it is going to be scrambling their signals at the first of the year, so you wouldn't be able to watch it anyway.

Q: How much will your service cost?

Jernigan: We have several different services and, consequently, the service will be offered in many combinations. Experience has shown that most subscribers elect to take a basic service plus two to four pay-TV services. This affords our subscribers the widest possible choice and variety of programming. Under our current rate schedule, this monthly amount would range between $25 and $35 a month.

Q: When should someone think about signing up?

Jernigan:; As we turn on [service in] each of our areas, we will be contacting those homes that we pass with a small direct-mail piece, telling them that a salesman will be contacting them. He, in turn, will come and offer them all of the selection capabilities of our services, and at the same time he will also notify the prospective subscriber that, if they hook up during that 30-day period, after their area is energized with cable, they can get installed free. No installation charges.

Q: What channels are you offering?

Jernigan: We will be offering all of the local network stations, all of the local independents as well as all the local educational stations. This will also include the Baltimore stations that a lot of the people in Washington like to watch. In addition, we'll be offering all the satellite channels, such as HBO, ESPN, Showtime, Cable News Network and the USA Television network. This is all included with the service. And, in addition to that, we'll also be offering local programming, access programming, and alpha-numeric information services via our community access channels.

Q: Why are some parts of the county going to get cable next year and other parts have to wait two or three years?

Jernigan: Well, obviously, the building program is three-and-a-half years. And we can't build it all at one time and so we look at it geographically. We have to build our cable systems in [a] certain technological manner. And so we designed the system to emanate out of what we call "hubs," which are fed by microwave signals. And that pretty much dictated the way the system would be built.

Q: So those closest to the hub will get service first?

Jernigan: Yes.

Q: What is a cable-ready TV?

Jernigan: Well, a cable-ready TV is a television set that has expanded channel reception capability. Most of the time it can pick up the VHF and the UHF signals and, in addition, it can usually pick up what we call the midband signals. Unfortunately, most cable-ready sets do not receive the superband signals that our cable system will be carrying. As a result of that, our subscribers will be provided a multichannel converter that will be able to receive all of the VHF-UHF midband and superband signals that we will be delivering.

Q: How will cable be brought into my home?

Jernigan: We will install cable into the home very much in the same way that . . . our subscribers currently receive their telephone and their power. If the telephone wires that service the home come in aerially, that is, above ground, we would do that same thing. If their wires come in underground, we go underground. . . .

Q: And if you have to go underground, do you dig up the yard?

Jernigan: Obviously, to facilitate getting the wires underground, there has to be a certain amount of excavation. There have been some new technologies in this underground construction in the last 10 years. We use a device commonly known as a vibratory plow, which has a minimal amount of soil disruption. And restoration of the soil is minimal.

I think one thing that should be mentioned here is that cable television is strictly an optional service. While we would like to think that everybody has to have it, we know that everybody doesn't have to have it. And one of the things that's very important is that when we do our construction we want to make sure that we make everybody happy. We do not want to upset anybody during the construction period. Because once I put my money in the ground, the last thing I want to do is destroy any opportunity that I might have of getting that subscriber. So we go way out of our way to make sure that, once we put our cables in, everyone's happy.

Q: What do you mean by "restoration of soils?"

Jernigan: Obviously, when we put the cable in, we disrupt the soil. In other words, we have to move the soil. "Restoration" means that, after the cable is underground, we pull all the soil back together, pack it down like it was and then reseed. . . .

Q: What if no one on my street wants cable except me. Does that rule me out?

Jernigan: It depends. In most cases, . . . the houses will be done on an individual basis. . . . We do absolutely everything that's humanly possible to figure a way to serve a subscriber who wants service.

Q: There may be sometimes, though, that the person is in an isolated area, where nobody else in that area wants cable, that it might be too expensive at this point. Is that a possibility?

Jernigan: Yes.

Q: A probability.

Jernigan: Under our franchise, . . . in those areas where it does not meet the minimum home density; we have language that makes it available for subscribers or perspective subscribers in low-density areas to contribute to the construction cost to help us get service to them. That was all put in the franchise.

Q: Do you recall what the density was?

Jernigan: If I remember correctly, the minimum density is 35 homes to the mile.

Q: Let's talk about the converter box on top of TV.

Jernigan: Media General will supply an expanded channel selector, known in our industry as a converter, as part of the service. The selector is a very attractive little box, usually has a walnut covering and it sits on top of the television set. It will descramble all the services that the individual wants.

In addition to that, these converters also have what we call remote capability. . . For those subscribers who would like have remote capability on their television sets, they will have the opportunity by going with our new channel selectors, which is really nice. . . .

Q: Should I prewire my home? Will that speed things up or save me money?

Jernigan: No, we don't recommend it. The cable system that we're building is extremely complex and requires very special cable to interface between our main cables on the poles and your television set. This high quality coaxial cable is expensive and it's difficult to install. In addition, Media General will only warrant and service the equipment that it installs, so consequently we do not encourage people to install their own wiring or their own materials, because we will not service it.

Q: How will I be billed?

Jernigan: We will bill our subscribers on what we call an anniversary basis. In other words, if you're hooked up on the 15th of the month, then on the 15th of every month, you will receive a bill for the services rendered. If you're hooked up on the 12th, you'll receive a bill for the 12th. . . . So that way everybody will be billed on the day they were installed and that makes it easier for the subscriber to understand because you don't get it prorate billing or any of that stuff.

Q: What will the charges be for those who did not sign up during the 30-day free installation time period?

Jernigan: . . . It depends on the amount of services that you take. Obviously, the more services that you take, the more the installation charges. But again, I think it's very important for prospective subscribers to remember that under the franchise agreement, we will install as much service as they want for the first 30 days of turn-on free.

And I wholeheartedly encourage any prospective customer to try every service that they think they might need. If you evaluate it for 60 or 90 days, you can always ask to have the service removed. There are no disconnect charges.

Q: So, in other words, if someone just takes the basic service and then six months later decides they want to add on, they're going to get some sort of installation cost. But, if they do it all at the beginning, they're not going to get the installation charge.

Jernigan: No installation charges, and that's a real plus.