CNN19980104.1600.0223 NEWS CAPTION adventurer steve fossett is having some technical problems in his bid to be the first person to circle the world nonstop in a balloon. fossett is now about 200 miles from istanbul and hopes to reach turkey by tonight. problems with a capsule heater are making for a cold ride. his staff is working on that problem and on fixing a malfunctioning remote control for one of the balloon's burners. earlier, a spokesman said fossett remains in good spirits. we've had reports from the mission control team that he's very upbeat. he's talked to a couple of crews on flybys, planes in the area. they've talked to him and mission control. he's very enthusiastic and very optimistic. fossett left st. louis, missouri, wednesday and expects the trip to take about two more weeks.