Good Day Last October at the Armadillo Intertie Annual meeting I attended an excellent presentation and live demo by Space Data Corp. The balloon was at about ninety thousand feet altitude somewhere east of Dallas and we talked with one of their engineers in Dallas via a 900 MHz HT from Austin, TX. The DSP in the balloon was reprogrammed from it's normal data mode to repeat voice FM for the demo, running about 3 watts on a low gain antenna. The balloon payload weighs a maximum of 6 pounds (per FAA), this includes the battery, TX/RX, a GPS to measure position in three dimensions, DSP and sand for ballast. It takes 1-2 hours for ascent to 90k feet, a valve releases excess helium to stop the ascent and then releases sand to compensate for helium leakage and maintain the altitude for the typical 12 hours of usable time. It takes 6 balloons to provide coverage and redundancy for all of Texas so in a 24 hour period some 12+ balloons are launched every day to ensure at least 6 are continuously at altitude. Payloads cost ~$1500 each and can be reused about 10 times, their recovery rate is around 90 percent and the payload sends it's GPS position back up to the balloons on orbit as they descend via parachute clear down to ground level. Their primary use has been for vehicle tracking and data collection.
Space Data Corp has been doing this 7/24 for over two years for Texas. This system is being evaluated for Mexican boarder patrol using something like seven balloons and also for military communications for all of Iraq. It should be interesting to see how well this works for cellular. These people are serious and know how to do this technology better than anyone else. Some of them are hams too! http://www.spacedata.net/ Bruce WB6ARE Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
