LAS VEGAS, Nev. (AP) _ Gimmicks abound at the nation's largest consumer electronics trade show this year as companies try to generate enthusiasm for products whose hot sales growth has slowed.

The annual winter Consumer Electronics Show, with $1 billion in gadgetry spread over display space the size of 20 football fields, proved again this week to be a veritable feast for the electronics crowd.

More than 1,400 companies were on hand, and those with an angle were once again drawing the crowds from the 105,000 buyers and sellers.

Sales of consumer electronics have stopped growing at double-digit rates and have reached a ''golden plateau,'' said William E. Boss, a vice president of RCA Corp.'s Consumer Electronics Division. He said sales grew 6 percent in 1985 and should grow about 5 percent this year.

The darlings of the winter show are videocassette recorders, or VCRs; video camera-recorders, or camcorders; satellite earth stations and video disk players - product lines that were too futuristic to comprehend two decades ago when the show began by featuring radios, televisionss and phonographs.

Boss predicted VCRs will be in 40 percent of American households by the end of 1986, up from 30 percent in 1985. Financial analysts predict slower growth, noting that the popularity of video disk players has taken some of the punch out of VCRs.

The predicted $35 billion in consumer electronics sales this year would be $2 billion higher than last year's record and would have a $50 billion impact on the nation's economy, almost 2 percent of the gross national product, Boss said.

Manufacturers hoping to catch the fancy of retailers at this year's show are again displaying ingenuity as well as product lines.

Playboy and Penthouse, which count on consumer electronics advertising as a major revenue source, turned to sexy ladies for their sizzle. Across the aisle, trade publications covering audio, video, computers and entertainment drew scant crowds.

Down the hall, Walt Disney Home Video had built a miniature castle to showcase wares aimed at the pre-Playboy crowd. Nearby, National Video had erected a miniature grocery store to display its latest techniques for reaching the booming video rental business.

Entertainer Anthony Newley was at the Video Gems booth, promoting the home video release of his Emmy Award-winning show ''Animal Talk,'' in which he stars as Dr. Doolittle, a veterinarian who can talk to his patients.

Smith Corona, touting a new typewriter with the ability to check the spelling on 35,000 words, conducted electronic spelling bees, pitting attendees against the machine. Royal was promoting a similar machine with an 80,000-word dictionary.

AT&T announced a cellular-based telephone designed for yachts, saying the new phone could be used to call any other phone in the world. Suggested retail: $2,995.

Citizen Watch Co. displayed a futuristic 3-D stereo-binocular space helmet developed for NASA with the use of Citizen LCD technology.

Tomy Corp. displayed eight robots with a variety of functions from pouring and serving drinks to providing wake-up calls.

BioTechnology Inc. displayed WristCoach, a wrist-worn pulse monitor which produces readings for runners and other athletes. Users can program a heart- rate warning level into the unit, which beeps if the heart rate gets too high.

Among the items on display by Sharp Electronics Corp. was Little Black Book I and II, pocket calculators with expanded functions to store names and phone numbers, shopping lists, appointments, etc.

Casio was pushing a wide range of products, from calculators to watches, musical instruments to pocket televisions.

Casio President John McDonald predicted $1 billion in sales this fiscal year.

''Music zoomed ahead of our other products this year,'' McDonald said of the company's line of keyboards. ''We never thought we'd have five years without a real competitor in the field. That's unusual in the electronics business. It's a testimony to our patent department.''

Show officials, mindful of the interest in Sunday's National Football League playoffs, placed 20 giant-screen TVs at key locations around the 18 acres of display space.

''We don't want those people leaving the show or staying in their hotel rooms Sunday,'' show founder Jack Wayman said of the show's closing day. ''We want to make sure they're here, looking at the merchandise, so we're bringing the playoffs to them.''