The moment the invitation to install cable television appeared in Mark Gilbert's Northwest Washington mailbox in November was one of pure joy. After years of waiting, cable had finally arrived in the District and Gilbert was ready.

With most District residents still waiting for cable to come to their neighborhoods, Gilbert belongs to an elite group of city video buffs in parts of Southeast, Northeast and Northwest who can tune in. But, as Gilbert has found, the road to cableland occasionally can be a bumpy one.

First, there was the matter of the Bravo entertainment channel advertised in the cable marketing brochure. Gilbert was interested, but employees at District Cablevision, the company that runs the District's fledgling cable system, could not explain what Bravo was, he said. Gilbert had to call the publishers of the cable program guide in Colorado, who steered him to the Bravo producers in New York.

Then there was the reception of local television channels that once had been so clear and suddenly got so fuzzy after Gilbert's television was hooked to cable. Unable to get through to Cablevision workers on the telephone, Gilbert took time off his job at the U.S. Department of Education in Southwest to ride by subway and bus across town to the company's offices on Florida Avenue NW, only to be turned away by a receptionist.

Finally, although Gilbert's state-of-the-art television was equipped for a direct link to the optional Bravo channel, Cablevision's equipment was not. Workers missed two appointments before finally installing additional devices that allow Gilbert to tune in Bravo, which specializes in fine arts programming. Now he's waiting to see whether Cablevision will bill him extra for the equipment he thought he would not need.

"It's been a bother that any sane person would have avoided, had they known what they were in for," Gilbert said. "I like the technology and I've put up with their various travesties so far, because of waiting for so many years. Now that we've got it, I just hope it gets better."

Gilbert's long list of complaints represents an extreme example of things that can go wrong with cable. Indeed, officials here and elsewhere contend that construction of the District's system so far has gone relatively smoothly compared with some other jurisdictions.

In Montgomery County, for instance, officials are still working to put the cable operation on a smooth track after a trouble-plagued effort by the original cable operator required intervention by a second company. Counties such as Fairfax and Arlington have had their share of troubles over such things as rate increases and public access to the cable network.

Elsewhere, officials report numerous problems with cable construction, including inconveniences caused by crews digging up streets to lay wires and damage to private property. Such problems could yet befall the District, these officials said. But they say the long experience of Chesapeake and Potomac Telephone Co. -- a partner in the D.C. cable venture -- probably has helped to avoid some of those pitfalls.

More than 13,000 D.C. householders, or about 30 percent of the available market, have signed up for the cable service since Cablevision started installations in late 1986. The complaint file at the D.C. Office of Cable Television, which monitors the city's franchise agreement with the company, contains reports from unhappy customers who are calling for help at a rate of about eight a week.

Richard Maulsby, director of the cable television office, said he is surprised there aren't more complaints -- a lot more.

"Building and marketing a system is a very difficult operation in an urban area," Maulsby said. "I have heard stories in some cities, like Boston, they were getting 100 calls a day."

Thomas Cohan, director of Boston's Office of Cable Communications, said complaints there have dropped sharply in the last year. Four years ago, the city recorded 4,600 complaints from among 68,000 subscribers. Last year, there were about 1,300 complaints, he said, among about 78,000 customers.

Cablevision officials attribute problems with the District's system to growing pains. Some technical and personnel glitches still need to be worked out as the city's cable network grows. But most customers, according to Cablevision marketing director Bruce Williams, are satisfied once they are plugged in.

About 1,000 subscriptions have been canceled since 1986, but 95 percent of those, Williams said, were canceled by the company after subscriptions weren't paid.

"Once you've got it, you never want to go back," said subscriber James Williams, who lives in Petworth. "It's like the difference between color and black-and-white television."

Williams' first impression of Cablevision wasn't so upbeat. Eager to get a cable hookup in time to watch the heavyweight boxing title match last month between Mike Tyson and Larry Holmes, Williams called Mayor Marion Barry's office after getting nowhere sparring with Cablevision's mechanical telephone-answering devices.

"I started calling around 9 o'clock in the morning. Then around 6 that night, I get a recording of {jazz singer} Anita Baker," Williams said. "That just got me so mad." Williams missed the fight.

In what may be the ultimate irony of a system for which so many clamored for so long, a group in Colonial Village in far Northwest near Rock Creek Park wants the cables strung on utility poles outside their homes to come down. They say the cables ruin their view.

"It's so ugly and so horrible," said Karen Shaner, spokeswoman for the Colonial Village group. Shaner, a psychologist, is host of a program called "Caring" on the Hearst Cable Network. "I've been told that Georgetown and Capitol Hill are complaining because they don't have theirs yet. Maybe they'd feel better if they came over here and saw what it looks like."

Cable industry officials are particularly sensitive about complaints because their marketing scheme depends heavily on word-of-mouth advertising. Cablevision officials expect to turn a profit with a 38 percent share of D.C. households, but are hoping to sign up half the city's television owners.

Cablevision, a partnership of local investors -- Chesapeake & Potomac Telephone Co. and Denver-based Telecommunications Inc., the country's largest cable operator -- began D.C. installations in Southeast because company officials said it was easiest there to rent space for equipment.

With cables laid east of the Anacostia River, the company moved its headquarters to the renovated Manhattan Laundry building near 14th Street and Florida Avenue NW, and began stringing lines in the area around Walter Reed Army Medical Center. From there, the system is supposed to spread out east and west like tree branches, eventually converging on the middle of the city until the District is entirely wired. Cablevision originally had targeted 1991 to complete the system, but now officials say they are running about a year ahead of schedule.

Before being awarded the cable franchise, Cablevision had promised a system with 78 channels. That has been pared to 54. Cablevision's original offer also included a two-way residential network for home shopping and other services, as well as a system for business communications, but those proposals have been put on indefinite hold.

For a monthly charge of $15, subscribers to Cablevision's basic service can tune in 42 channels with programs ranging from coverage of Congress and the D.C. Council to rock videos and entertainment aimed at black audiences. There are variety programs for children, home study courses, documentaries and a steady onslaught of movies.

A $31.45-a-month package includes Home Box Office, Showtime and the Disney Channel. Subscribers can add any of three other entertainment channels -- Bravo, the Movie Channel and Cinemax -- for $10 each. Cablevision charges $30 for the initial installation.

While marketing director Williams estimates that 85 percent of installations take place without a hitch, he acknowledges several problems, some more severe than others.

For instance, Cablevision officials decided it was not economical to hire full-time technicians to perform home installations. Instead, the company relies on four subcontractors to do the job. Not every installer is as punctual as the company would like. Some orders simply get lost in paperwork at the Cablevision offices.

Reception of local channels sometimes goes bad, Williams said, when individual television tuners interfere with the cable signal. There were more widespread problems last year when Cablevision was receiving local transmissions from an antenna on its roof on Florida Avenue. The antenna has since been moved to a 140-foot tower nearby, which cleared up Mark Gilbert's picture.