Castaway spacesuit radio experiment still alive
BY SPACEFLIGHT NOW
Posted: February 4, 2006
Reports that the amateur radio equipment tucked aboard the discarded Russian spacesuit launched by spacewalking astronauts Friday had stopped transmitting have proven premature, project officials said Saturday, amid reports from around the world of hearing very weak signals from the orbiting object.
International Space Station commander Bill McArthur and flight engineer Valery Tokarev fitted the wornout Orlan suit with battery-powered ham radio gear designed to broadcast pre-recorded messages in Russian, English, Japanese, Spanish, German and French, a Slow-Scan Television image and telemetry data, including the suit's temperature and the battery voltage, as part of an educational experiment.
Early reports soon after the deployment indicated that SuitSat's signals were being detected by listeners in Japan and elsewhere. But the transmissions were weak. Within a couple of hours, officials said the signals had ceased completely. It was speculated that the batteries had gotten too cold, shutting down the radio equipment.
Despite the bleak news, attempts to hear SuitSat on 145.990 MHz continued Saturday in hopes of detecting any communication. Those efforts paid off with reports across the globe of faint, intermittent signals being picked up when the suit flew overhead.
"Paraphrasing Mark Twain....the demise of SuitSat-1 is highly exaggerated!!" a project news release said Saturday evening.
"It is now nearly 24 hours since the successful deployment of the SuitSat-1 experiment. These past 24 hours have been a wild ride of emotions...tremendous highs...deep lows when people reported no signals and said SuitSat-1 was dead and now....some optimism.
"It is absolutely clear that SuitSat-1 is alive. It was successfully turned on by the ISS crew prior to deploy and the timing, micro-controller functions and audio appear to be operating nominally. The prime issue appears to be an extremely weak signal.
"I have heard several recordings and have monitored two passes today. When the signal is above the noise level, you can clearly hear partials of the student voices, the station ID and the SSTV signal. One of the complicating factors in reception is the very deep fades that occur due to the spin of SuitSat," Frank Bauer, international chairman of the Amateur Radio on the International Space Station (ARISS) program, wrote in Saturday's news update.
"Based on the information we know thus far, one can narrow down the issue to the antenna, the feedline, the transmitter output power and/or any of the connections in between. Through your help, we would like to narrow down the issue further and also gather some internal telemetry from the Suit. If the transmitter is running at full power, we would expect the Suit to end operations in the next few days to a week. If it is not, then it will operate much longer.
"Since we do not know how long this experiment will last, we ask for those with powerful receive stations to listen for SuitSat -- especially during direct overhead passes when the Suit is closest to your area. If you can record these passes and send the audio to us, it would be most appreciated. We will continue to be optimistic that this issue will right itself before the batteries are depleted. So please KEEP LISTENING!"
The news release gave these guidelines to listeners trying to hear SuitSat:
1) You need as high a gain antenna as possible with mast mounted pre-amps. An arrow is the minimal set...it provides very brief snippets of the communications. HTs and scanners won't cut it.
2) I would not waste your time on passes below 40 degrees elevation. SuitSat is too far from your station to receive a reliable signal. We have found that closest approach provides several seconds of SuitSat communication with 22 element yagis.
3) The "gold" we are looking for right now is the telemetry information and how long the vehicle stays operational. So if you hear any of the telemetry, please let us know.
NASA's J-Pass satellite tracking utility can be used to determine roughly when SuitSat will be within range of your location: http://science.nasa.gov/RealTime/JPass/25/JPass.asp.
SuitSat project leaders are asking that anyone hearing the transmissions post a report at http://www.suitsat.org.
"SuitSat-1/Radioskaf is a space pioneering effort. Pioneering efforts are challenging. Risk is high. But the future payoff is tremendous. As you have seen, we have not had total success. But we have captured the imagination of the students and the general public. And we have already learned a lot from this activity. This will help us and others grow from this experience," Bauer wrote.
"Keep your spirits up and let's continue to be optimistic. And please keep monitoring!!"