October, 2006

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ISS Crew, ARISS Team Troubleshooting Slow-Scan TV System
The Amateur Radio on the International Space Station (ARISS) team is coordinating with Expedition 13 Commander Pavel Vinogradov, RV3BS, and ARISS-Russia's Sergei Samburov, RV3DR, to troubleshoot the slow-scan television (SSTV) system onboard the ISS. The SSTV system remains off the air for the time being.
"The ARISS team is coordinating with Sergei Samburov and Pavel Vinogradov to resolve some of the issues seen when the SSTV system was hooked up," ISS Ham Radio Project Engineer Kenneth Ransom, N5VHO, told ARRL. Photos of the current SSTV configuration that were downlinked to Earth showed "several unanticipated results" from the initial tests, Ransom said. "More extensive troubleshooting is being developed and could further delay permanent activation of the radio." He added that it could take a long time to work out the kinks because Vinogradov is only able to work on the system in his free time. Vinogradov will return to Earth in September.
ARISS International Chairman Frank Bauer, KA3HDO, earlier this month echoed Ransom's assessment, indicating that ARISS expected SSTV system testing to continue over the next few weeks. "Since this is a 'spare time' activity for Pavel, please bear with us as we go through this aspect of system setup," he said on the SAREX reflector in mid-August. "It is not possible right now for Pavel to switch between modes (eg voice, packet and SSTV) on the Kenwood and continue the methodical process of system setup and reconfiguration."
The SSTV system uses the ARISS Phase 2 station, a modified Kenwood TM-D700E. In recent weeks, ARISS has been using the Phase 1 station, an Ericsson hand-held transceiver, to conduct contacts with schools, since the Phase 1 antenna system is more favorable given the space station's current attitude with respect to Earth.
During the early stages of SSTV testing in late July, Earth station operators were thrilled to receive several pictures Vinogradov was able to transmit manually on 2 meters (the system has been using 144.490 and 145.800 MHz) using the RS0ISS call sign. Ransom says initial tests were run over Moscow, and then the system was left on for a few orbits.
Plans call for Vinogradov -- as his schedule permits -- to continue checking out the SSTV software, configure and optimize the radio and perform integration checks necessary. So far, the SSTV system has been unable to function properly in the autonomous "slide show" mode, Ransom said.
Miles Mann, WF1F, who developed the SSTV system as an ARISS project, explains that slide-show mode will permit the crew to preload a directory of images that then will automatically transmitted to Earth. "The crew will not need to keep pushing a button to send images," he said in a recent news release. "In theory, the system can run for weeks at a time without crew involvement."
The SSTV system is not yet configured to receive SSTV transmissions from Earth stations, and no uplink frequency will be made public until testing is done. Earthbound radio amateurs are advised not to attempt to transmit SSTV images to the ISS.
Mann says future ISS crews will use newly developed SpaceCam1 software to enhance the SSTV system and experience for Earth stations. He says SpaceCam1 permits transmission of SSTV images via Amateur Radio primarily using the Robot 36 format.
"One of the key features of the software is that it allows two-way interactive operation," Mann says. "The software also fully automates the transmission of images and use of SSTV repeaters." Mann has posted detailed information about the SSTV project on his Web site.

Long-Silent SuitSat-1 Keeps Going and Going
When SuitSat-1 -- the satellite built in a surplus Russian Orlan spacesuit -- was launched during a spacewalk from the International Space Station last February 3, those familiar with orbital mechanics predicted it would stay in orbit for 120 days at best. Today, some 202 days (nearly seven months) later -- largely forgotten and its ham radio voice long since silent -- SuitSat-1 has defied the odds and remains in orbit some 164 miles above Earth.

Maine's Governor is Now KB1NXP
Maine Gov John E. Baldacci may now be the only sitting state chief executive holding an Amateur Radio license. Following up on an effort begun a few years ago, Baldacci took and passed his Technician license test September 6, and the FCC issued his new call sign, KB1NXP, today.

October, 2006

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