ACTOR BARRY NELSON, who is currently appearing in "The Dining Room" at the Eisenhower Theater, is a passionate traveler. For the past 15 years, he has spent four months a year acting mostly to pay the bills for the other eight months when he travels. "This planet is a spaceship of limited duration," he explains, "and I like acting, but there is not that much work that is really fun to do."

When he travels, which he usually does by himself and without announcing who he is or what he does, he looks for material he can use as an actor. "What you learn about technique begins to narrow, but really learning about people is always a great challenge."

In the past few years, he has preferred traveling to faraway places such as Asia, South Asia and South East Asia, where he has been twice in the last eight months. "Three guest shots on 'Dallas' did that for me," he says happily. Some of his favorite jaunts and the experiences that intrigued him have been:

Bahrain: "When I got off the India-bound 747 in Bahrain, there were only two other people leaving the plane and they had briefcases. They asked me why I was there, and I said I was just looking around. 'In Bahrain?' they said in disbelief. But it's one of those wild things you just do. I stayed a couple of weeks to see what was unraveling.There is feverish activity -- they're tearing down the city in order to build skyscrapers and gear up for manufacturing; they're bringing in labor from India and China. It's interesting to put it together yourself and see it unfold instead of reading it in the papers."

Delhi: "I don't stay in known hotels; I don't travel as an actor and I use local transportation. I stayed in a little Indian hotel in Old Delhi -- it was a wonderful kaleidoscope of sights and sounds. Then, when I left the city, I was breathing a sigh of relief, and on the way back to the airport, I was ambushed in my taxi by the taxi driver right in the middle of the city. I was able to flatten him."

Haiti: "I go to Haiti a good deal. The People are great, and it's a terrific short trip when you don't have a lot of time. There isn't anyplace nearby with a more dramatic difference in the life style. You have a feeling of being a long, long way from everything you know and it gives you a better perspective."

Tokyo: "It's extremely fascinating, but a hard place to get around, though you can learn the subway system in a couple of hours. The first time I was there I wanted to go to Shinjuku -- it's a section like our Greenwich Village, and also like their Ginza. It was late at night and a little cold. I saw these signs that said 'Hotel,' but I couldn't find the entrance. I didn't know they were called 'love hotels' and with their little blue lights they were really charming once I found the lobby. The Japanese all laughed at the American who bought several hours all on his own."