A 1600 gram weather balloon filled with hydrogen is let loose towards the heavens with its payload of fast-scan and slow-scan amateur television transmitters and an amateur radio tracking beacon Saturday during the 9th annual Yuma Hamfest held at the Yuma County Fairgrounds. The balloon, which was expected to burst at 90,000 feet or more, was to be in flight for approximately 90 minutes and travel up to 50 miles to the east before deploying a parachute to safely return the payload back the earth's surface.