-- 11220 Georgia Ave., Wheaton. 933-2525. Open: for lunch Tuesday through Friday 11 a.m. to 3 p.m.; for dinner Tuesday through Thursday 5 to 9:30 p.m., Friday 5 to 10:30 p.m.; Saturday 11 a.m. to 10:30 p.m., Sunday 11 a.m. to 9 p.m. Closed Monday. AE, MC, V. No reservations on Friday and Saturday evening. Separate non-smoking section. Prices: lunch appetizers $2.75 to $6.95, entrees $4.50 to $6.50; dinner appetizers $4.25 to $6.95, entrees $5.25 to $11.95. Full dinner with beer, tax and tip about $14 to $23 per person.

THE WHEATON TRIANGLE, A PIZza-shaped wedge of real estate, is a cat's cradle of telephone wires and tacky shopping strips, punctuated here and there by islands of urban renewal. Let's hope the renewal doesn't proceed too quickly because the triangle has become a haven over the years for shoestring ethnic shops and restaurants. One of the latest is Nam's, a fine but tiny Vietnamese place.

Before you rush out and put Nam's on the map, keep its limitations in mind. This is a plain-Jane little restaurant, cheerful, cozy and immaculately clean, but without the elegance of East Gate, the Vietnamese restaurant around the corner. Nor does it have East Gate's extensive menu -- Nam's is a conservative place, offering a limited number of the same standard Vietnamese dishes you'll find in restaurants all over town.

Sound dull? It isn't, because what Nam's does it does remarkably well. Granted, the quality control can be a little erratic, but the stumbles are offset by some outstanding items. And, as with most Vietnamese restaurants, there's the comfort of caring, eager-to-please service and very reasonable prices.

Nam's appetizer list seems less for midable if you break it down into groups. First there are the rolls. If you're tired of oil-soaked spring rolls, Nam's version, with properly crackly wrappers and dynamite fillings, ought to perk you up. Then there are the cold summer rolls, delicate rice paper pancakes wrapped around shrimp, pork, vermicelli noodles, cilantro and sprouts. (The special salad is essentially the summer roll filling without the wrapper.)

The next category is the shrimp puree appetizers, all nicely done. The best is the shrimp cake, in which the flavorful, fresh-tasting puree, heady with garlic and pepper, is heaped on a thin slice of French bread and deep fried. Another, less appealing version combines the fried puree with small, not-very-meaty crab claws. Still another variation is an excellent rendition of the traditional grilled shrimp puree on sugar cane, the shrimp wrapped at the table in rice paper pancakes with cilantro, romaine and mint -- another variant of the summer roll, and a lovely combination. Butterfly shrimp occupies its own category: whole shrimp fried in a thick but crisp batter with the clean taste of fresh oil.

Then there are the grilled meat appetizers. A standout is the beef in grape leaves, Vietnam's answer to dolmades, in which juicy, rough-ground beef and sesame seeds are wrapped in fine-textured grape leaves and gently grilled so the leaves are faintly crisp. The pork on skewers is top-notch too, nicely marinated, slightly sweet with honey. But we found the skewered beef, similarly marinated, to be quite dry -- surprising in view of the other excellent beef dishes.

The soups here shouldn't be missed. Pho, the traditional northern Vietnamese beef soup, is a robust winner, with a meaty broth, firm noodles and beef that's thinly sliced yet a little rare.

Fisherman's soup is as delicate as the pho is hearty: Light, clear, virtually fat-free, it combines big chunks of fresh fish with pineapple, fresh tomato, cilantro and sprouts. The most interesting of the group is the meatball soup, a light chicken broth with lovely meatballs that you dip in a side dish of hoisin and chili sauce. The least interesting is the Saigon meat soup.

One of the best entrees in the house is the roast quail, an occasional special. Marinated in a peppery sauce with anise, the birds are beautifully grilled so they're crisp outside, moist and tender within. Another superb entree is the steamed fish, a fresh whole snapper topped with vegetables and noodles, perfectly cooked so it flakes off the bone in pearly chunks. Just as outstanding is the bo dun, very thin beef slices marinated in wine and honey, then wrapped around pieces of onion and grilled. Good but less notable is the Vietnamese steak, also nicely marinated but a little overcooked when we tried it. Lemongrass beef with coconut milk is a complex delight, its beef chunks a perfect delivery system for the tart-hot-gingery flavors of the sauce. Another beef treat, this time light and delicate, is the Hanoi beef saute, with tender meat, lively vegetables and a subtle but meaty lemon grass-garlic sauce. Also with a gentle sauce is curry chicken, reminiscent of a homey stew, with onion, potatoes and carrots.

There are a few entrees similar to the grilled appetizers. Grilled pork on rice crepes is excellent, the thick, glutinous crepes a new but easily acquired taste. Lemon chicken (no relation to the Chinese dish of the same name) is juicy, tender and gently flavored. The pork chop (no relation to the American meat of the same name) is a pounded piece of pork of no great character, and the "pork skin" dish resembles pulled pork barbecue minus the oomph -- again, nothing much. Minced pork, on the other hand, is excellent, crisp-surfaced and juicy. Although the shrimp here aren't superb, they're nicely plump and fresh-tasting. Mekong shrimp, in a zingy tomato-based sauce, are particularly appealing.

The best of the noodle dishes is the golden noodles, very thin vermicelli with a light crunch and a faintly toasted flavor, with a slightly thickened, Chinese-style sauce, used sparingly to set off the noodles without making them soggy. The rice noodle special, on the other hand, is pretty dull, the broad noodles glued together in a ponderous clump.

A couple of disappointments: Both the shrimp and scallops on skewers and "golden coins," another skewered dish, were somewhat dry (on the same night, probably a quality control slip-up). But the biggest bust was the ginger chicken, with a brassy, very salty sauce and no discernible ginger flavor.

Desserts include a dense but delicate flan and very good banana and pineapple flambes with nicely sweet, boozy sauces. The steamed banana cake, on the other hand, is hard to love.

Finally, a word of advice: Don't everybody go at once. Remember, this is a fragile, family-run restaurant, easily overwhelmed. And don't be put off by the ramshackle neighborhood. Nam's is a jewel in a tarnished setting.

Mark Barnett; Gail Barnett are freelance restaurant critics. Phyllis C. Richman is on vacation.