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 Previous: More Cosponsors Sign Aboard CC&R Bill HR 4720 |  Next: ARES Teams on Alert as West Coast Wildfires Threaten |
NEWINGTON, CT, Aug 2, 2002--The mystery command operator of the recently resurrected AO-7 satellite is none other than satellite veteran and AMSAT Principal Satellite Investigator Mike Seguin, N1JEZ, of Burlington, Vermont. After being inactive for more than 20 years, AO-7 was discovered back on the air in June and at least semi-operational. Seguin subsequently stepped in to handle Earth station duties but initially kept a low profile.
 Covert AO-7 Command Operator: AMSAT Principal Satellite Investigator Mike Seguin, N1JEZ, during an AO-40 presentation earlier this year in Vermont. [ARRL Photo] |
"I guess it's time for me to step forward out of the shadows," he announced in July. "I'm the so-called 'Covert AO-7 Command Operator.'" Seguin said he stayed undercover for a while because he did not want to have to deal with "the inevitable flood of e-mail" while concentrating on a critical phase of trying to command AO-7. "There were a number of technical hurdles to overcome," he said, "not the least of which is dealing with 30-year-old stuff."
AO-7 was launched November 15, 1974, and it remained operational for more than six years before suffering battery failure in 1981 and going silent.
Although Pat Gowen, G3IOR, first announced the reappearance of AO-7 on June 21, Seguin now believes the aged spacecraft may already have been back in operation for a year or so. "For the past year or so, during East Coast passes of UO-14, I've heard CW come through the transponder," Seguin said this week in a posting to the AMSAT reflector. "I never paid any attention . . . until recently!"
Seguin said he's now convinced that the CW he heard--and continues hearing--during UO-14 passes is from AO-7 in Mode B, transmitting on approximately 145.973, very close to UO-14's 145.975 uplink.
"I wonder how long AO-7 really has been back, and we just didn't know it?" he asked.
Seguin told ARRL that AO-7 has been continuing to operate almost routinely. "It's still business as usual for AO-7," he said this week. "When sunlight hits the solar panels, it usually comes on, although there have been a few instances when nothing was heard."
Seguin says his job has been to investigate which AO-7 commands still work after more than two decades and which do not. "It's really exciting, but tedious, work," he said. "Imagine the thrill of seeing this antique accept your first command after all these years! I've gone from techno to retro in a short period of time."
He successfully commanded AO-7 for the first time on July 11, changing the CW beacon speed. So far, the satellite has been sent and has accepted at least seven different commands.
Seguin says he continues to "bang away," as he put it, in his efforts to maintain control over the elderly bird. "At this point, there are things that don't seem to work," he said. "I guess we have to expect that after 21 years."
Seguin says he's most interested in knowing how AO-7 "wakes up" as it enters sunlight. The satellite appears to be operating primarily from its solar panels, not its batteries. He also wants to know about any observations of simultaneous multiple modes. "Yoshi Imaishi, JF6BCC is compiling an excellent list of observations," he said. "Please send him whatever you have."
AO-7 orbit/mode historical data are available in spreadsheet form on the Internet.
Seguin said he's hoping to be able to do a presentation on AO-7's resurrection at the AMSAT-NA Symposium this November in Fort Worth, Texas.
Built by a multinational team under the direction of AMSAT-NA, AO-7 carries Mode A (145.850-950 MHz uplink; 29.400-500 MHz downlink) and Mode B (432.180-120 MHz uplink; 145.920-980 MHz downlink) linear transponders plus beacons on 29.502 and 145.973 MHz.
For those attempting to use AO-7, Mode A (2 meters up/10 meters down) is not a problem, but Mode B (70 cm up/2 meters down) is. Because of changes in the international Radio Regulations that went into effect in the 1970s as AO-7 was under construction, the 432.1 MHz uplink frequency is no longer authorized for space communications.
AMSAT advises potential users that when uplinking to a satellite, they are operating in the Amateur-Satellite Service. Sections 97.207(c)(2) and 97.209(b)(2) of the FCC's rules authorize space station and earth station operation only in the 435-438 MHz segment.
AMSAT has additional information on
AO-7 on its Web site.
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