Look at B-11 flight http://leobodnar.com/balloons/B-11/
solar rechargable battery, about 10g payload, and 187 hours flight :-)
We are not 100% sure the flight is over, maby there are no SWL'ers to listen :-)
solar rechargable battery, about 10g payload, and 187 hours flight :-)
We are not 100% sure the flight is over, maby there are no SWL'ers to listen :-)