[amsat-bb] OSCAR-11 Report
OSCAR-11 30th BIRTHDAY REPORT OSCAR-11 (AKA UoSAT-2 and UO-11) celebrated it's 30th birthday in space on 01 March! It was designed, built and launched within a period of six months, using commercially available 'off the shelf' components (COTS). Once again, congratulations to Professor Sir Martin Sweeting G3YJO, his team at the University of Surrey and the groups of radio amateurs who also contributed to the project. This report covers the period from 01 January 2013 to 05 March 2014. During this time there have been no significant changes apart from the gradual drift of the on-board clock. There was also an advance of one day in the displayed date. This was caused by a known leap year problem in the date chip, which has always existed since launch. Owing to the large accumulated time/date error 29 February 2012 on the satellite occurred in January 2013 on earth! The satellite has been transmitting on a regular cycle of 10.35 days on followed by 10.35 days off. Good copy has been obtained obtained from decoded telemetry frames and many reports have been posted on the DCARR general satellite status website, The satellite continues to be subjected to eclipses during each orbit, resulting in weaker signals at those times. During the winter in the UK the evening passes were in the earth's shadow, and very weak signals have been received, which could not be demodulated and could be only detected with the receiver in CW mode . As the longer daylight hours of summer approach, the evening passes in the UK should gradually become clear of eclipses, resulting in stronger signals. Eclipses are expected to continue until 2019. The on-board clock gained 98 seconds during the 14 month reporting period, which is comparable with the 60 seconds gain per year when the satellite was launched. There is however a large accumulated error of 307.54090 days slow. This was caused mainly by the clock stopping during eclipses, when there was also an unknown drain on the power supply. The units of the least significant digit correspond approximately to seconds (0.86 seconds actually). At the present time, while OSCAR-11 is operating in a predictable way, please DO NOT send reports or files by e-mail. However, could all listeners continue to enter their reports on the general satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest, especially for times 13:00 to 18:00 and 22:00 to 08:00 UTC, to when the satellite is out-of-range in the UK . The URL is http://oscar.dcarr.org/index.php The VHF beacon frequency is 145.826 MHz. AFSK FM ASCII Telemetry. The satellite is operating in the default mode, controlled by the watchdog timer, with a cycle time of 20.7 days. 10.35 days on followed by 10.35 days off. An extended version of this report is available on my website, and new listeners to OSCAR-11 should read this for further information. The URL is www.g3cwv.co.uk/oscar11.htm . This page contains links to the report, a short audio clip to help you identify the satellite and a file of recent telemetry received. The website also contains an archive of news telemetry data which is updated from time to time, and details about using a soundcard or hardware demodulators for data capture. There is also software for capturing data, and decoding ASCII telemetry. The easiest way to check whether OSCAR-11 is operational is to look at the General Satellite Status website http://oscar.dcarr.org/index.php . If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT159.CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace the x's by g3cwv) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 29 December 2011 This report covers the period from 01 September to 28 December 2011. The satellite has continued to operate in a very predictable way since the last report, and no changes have been observed. During this time the satellite has been heard reliably during its ten-day transmission periods. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. The easiest way to check whether OSCAR-11 is operational is to look at the General Satellite Status website http://oscar.dcarr.org/index.php . You can also calculate the operating schedule from the last switch-off time, which was 28 December 2011 at 15:00 UTC (approx), using 10.35 days off followed by 10.35 days on. Reception reports have been received from Gustavo LW2DTZ, Bob KI0G, Rolf HB9TSO and Francesco IT9JRU. Many thanks to all and those who posted to the status website. The satellite is currently in eclipse during all evening passes over the UK, resulting in lower signal strengths at these times. Owing to the gradual precession of the orbit, the season for eclipses of the evening passes is longer this year compared with the winter last year. The on-board clock continues to gain, 28 seconds during the current reporting period, and 112 seconds since regular transmissions were resumed at the end of August 2010. There is however a large accumulated error of 308.54303 days slow. This was caused mainly by the clock stopping during eclipses, when there was also an unknown drain on the power supply. The units of the least significant digit correspond approximately to seconds (0.86 seconds actually). The VHF beacon frequency is 145.826 MHz. AFSK FM ASCII Telemetry. The satellite is operating in the default mode, with a cycle time of 20.7 days. 10.35 days on followed by 10.35 days off. At the present time, while OSCAR-11 is operating in a predictable way, I no longer need direct reports or files by e-mail. However, could all listeners continue to enter their reports on the general satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest, especially for times 12:00 - 18:00 and 22:00 - 07:00 UTC, when the satellite is out-of-range in the UK . The URL is http://oscar.dcarr.org/index.php A longer version of this report report is available on my website, and new listeners to OSCAR-11 should read this for further information. The URL is www.g3cwv.co.uk/oscar11.htm . This page contains a links to the longer report, a short audio clip to help you identify the satellite and a file of the last telemetry received. The website also contains an archive of news telemetry data which is updated from time to time, and details about using a soundcard or hardware demodulators for data capture. There is also software for capturing data, and decoding ASCII telemetry. If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT157.CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace the x's by g3cwv) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 01 September 2011 This report covers the period from 27 April to 01 September 2011. The satellite has continued to operate in a very predictable way since the last report, and no changes have been observed. During this time the satellite has been heard reliably during its ten-day transmission periods. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. The easiest way to check whether OSCAR-11 is operational is to look at the General Satellite Status website http://oscar.dcarr.org/index.php . You can also calculate the operating schedule from the last switch-off time, which was 26 August 2011 at 08:00 UTC (approx), using 10.35 days off followed by 10.35 days on. Reception reports have been received from David VE3SB, Jerry WB5LHD, Toby MM0TOB, Colin VK5HI and Lee M0HOK. Many thanks to all and those who posted to the status website. Although eclipses occur during every orbit, the evening passes over the UK were mostly clear of eclipses, owing to the longer hours of daylight during the Summer months. This resulted in stronger signals during the evening passes. However, as winter approaches eclipses will now start to affect the evening passes. The on-board clock continues to gain, 26 seconds during the current reporting period, and 83 seconds since regular transmissions started at the end of August 2010. There is however a large accumulated error of 308.54339 days slow. This was caused mainly by the clock stopping during eclipses, when there was also an unknown drain on the power supply. The units of the least significant digit correspond approximately to seconds (0.86 seconds actually). The VHF beacon frequency is 145.826 MHz. AFSK FM ASCII Telemetry. The satellite is operating in the default mode, with a cycle time of 20.7 days. 10.35 days on followed by 10.35 days off. At the present time, while OSCAR-11 is operating in a predictable way, I no longer need direct reports or files by e-mail. However, could all listeners continue to enter their reports on the general satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest, especially for times 12:00 - 17:00 and 22:00 - 07:00 UTC, when the satellite is out-of-range in the UK . The URL is http://oscar.dcarr.org/index.php A longer version of this report report is available on my website, and new listeners to OSCAR-11 should read this for further information. The URL is www.g3cwv.co.uk/oscar11.htm . This page contains a links to the longer report, a short audio clip to help you identify the satellite and a file of the last telemetry received. The website also contains an archive of news telemetry data which is updated from time to time, and details about using a soundcard or hardware demodulators for data capture. There is also software for capturing data, and decoding ASCII telemetry. If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT156.CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace the x's by g3cwv) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 27 April 2011 This report covers the period from 02 March to 27 April 2011 . During this time the satellite has been heard from 03 to 13 March, 24 March to 03 April, 13 April to 23 April 2011. It is expected to switch-on again 04 May until 14 May. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. Transmissions are controlled by the watchdog timer, which has a 20.7 day cycle time, 10.35 days on, 10,35 days off. Solar eclipses occur during every orbit, when signals are weaker. This indicates that there is still some capacity remaining in the battery. The on-board clock is now very stable. It gained 12 seconds during during the current reporting period. This is comparable with its accuracy when the satellite was fully operational, when it gained approximately one minute per year. However, there is still an accumulated loss of 309 days, which has occurred during eclipses of the last few years. The VHF beacon frequency is 145.826 MHz. AFSK FM ASCII Telemetry Reception reports have been received from Horatio CX8AF, Jerry WB5LHD and Stefano IZ1GRJ. Many thanks. At the present time, while OSCAR-11 is operating in a predictable way, I no longer need direct reports or files by e-mail. However, could all listeners continue to enter their reports on the general satellite status website http://oscar.dcarr.org/index.php. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest, especially for times 12:00 - 17:00 and 22:00 - 07:00 UTC, to when the satellite is out-of-range in the UK. A longer version of this report report is available on my website, and new listeners to OSCAR-11 should read this for further information. The URL is www.g3cwv.co.uk/oscar11.htm . This page contains a links to the longer report, a short audio clip to help you identify the satellite and a file of the last telemetry received. The website also contains an archive of news telemetry data which is updated from time to time, and details about using a soundcard or hardware demodulators for data capture. There is also software for capturing data, and decoding ASCII telemetry. If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT155.CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace the x's by g3cwv) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 04 March 2011 OSCAR-11 celebrated it's 27th birthday on 01 March! It was designed, built and launched within a period of six months, using commercially available 'off the shelf' components (COTS). Once again, congratulations to Professor Sir Martin Sweeting G3YJO, his team at the University of Surrey and groups of radio amateurs who also contributed to the project. Unfortunately, the satellite wasn't transmitting on its birthday, but resumed transmissions, three days later. This report covers the period from 31 January to 04 March 2011. During this time the satellite has been heard from 10 to 21 February and from 03 March 2011. It is expected to switch-off again 13 March until 23 March. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. The satellite is now transmitting during eclipses, although signals are weaker at those times. This indicates that there is still some capacity remaining in the battery. The on-board clock is now very stable. It gained *** seconds during the current reporting period. The VHF beacon frequency is 145.826 MHz. AFSK FM ASCII Telemetry At the present time, while OSCAR-11 is operating in a predictable way, I no longer need direct reports or files by e-mail. However, could all listeners continue to enter their reports on the general satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest, especially for times 12:00 - 17:00 and 22:00 - 07:00 UTC, to when the satellite is out-of-range in the UK . The URL is http://oscar.dcarr.org/index.php A longer version of this report report is available on my website, and new listeners to OSCAR-11 should read this for further information. The URL is www.g3cwv.co.uk/oscar11.htm . This page contains a links to the longer report, a short audio clip to help you identify the satellite and a file of the last telemetry received. The website also contains an archive of news telemetry data which is updated from time to time, and details about using a soundcard or hardware demodulators for data capture. There is also software for capturing data, and decoding ASCII telemetry. If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT154.CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace the x's by g3cwv) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 31 January 2011 This report covers the period from 31 December 2010 to 31 January 2011. During this time the satellite has been heard from 31 December 2010 to 10 January 2011, and from 21 January to 30 January . It is expected to switch-on again 10 February for ten days, and remain silent for the remainder of the month. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. The satellite is now transmitting during eclipses, although signals are weaker at those times. This indicates that there is still some capacity remaining in the battery. The on-board clock is now very stable. It gained eight seconds during January. The VHF beacon frequency is 145.826 MHz. AFSK FM ASCII Telemetry Reception reports have been received from Christian SWL-CHMY, Mike DK3WN, Campo PY5JAP, Ron WB0SOK and Horatio CX8AF. Many thanks for those and to everyone who posted reports on the satellite status website. At the present time, while OSCAR-11 is operating in a predictable way, I no longer need direct reports or files by e-mail. However, could all listeners continue to enter their reports on the general satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest, especially for times 12:00 - 17:00 and 22:00 - 07:00 UTC, to when the satellite is out-of-range in the UK . The URL is http://oscar.dcarr.org/index.php A longer version of this report report is available on my website, and new listeners to OSCAR-11 should read this for further information. The URL is www.g3cwv.co.uk/oscar11.htm . This page contains a links to the longer report, a short audio clip to help you identify the satellite and a file of the last telemetry received. The website also contains an archive of news telemetry data which is updated from time to time, and details about using a soundcard or hardware demodulators for data capture. There is also software for capturing data, and decoding ASCII telemetry. If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT153.CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace the x's by g3cwv) ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 31 December 2010 At the present time OSCAR-11 (AKA UO-11 or UoSAT-2) is now in a very stable and predictable mode of operation. There are very few changes taking place at the present time, I have therefore decided to limit the size of the monthly reports to a short status report. The full monthly report will still be available on my website, and new listeners to OSCAR-11 should read this for further information. The URL is www.g3cwv.co.uk/oscar11.htm . This page contains a links to the longer report, a short audio clip to help you identify the satellite and a file of the last telemetry received. The website also contains an archive of news telemetry data which is updated from time to time, and details about using a soundcard or hardware demodulators for data capture. There is also software for capturing data, and decoding ASCII telemetry. This report covers the period from 30 November to 31 December 2010. During this time the satellite has been heard from 10 to 20 December and from 31 December. It is expected to switch-off on 10 January 2011. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. The satellite is now transmitting during eclipses, although signals are weaker at those times. This indicates that there is still some capacity remaining in the battery. The on-board clock is now very stable. It gained seven seconds during December. The VHF beacon frequency is 145.826 MHz. AFSK FM ASCII Telemetry Reception reports have been received from Horatio CX8AF, John KB2HSH, Francisco PY9FP and Mike DK3WN . Many thanks for those and to everyone who posted reports on the satellite status website. At the present time, while OSCAR-11 is operating in a predictable way, I no longer need direct reports or files by e-mail. However, could all listners continue to enter reports on the general satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest. The URL is http://oscar.dcarr.org/index.php If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT152 .CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace the x's by g3cwv) ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 30 November 2010 This report covers the period from 29 October to 30 November 2010. During this time the satellite has been heard from 30 October to 09 November and 19 to 29 November . At the time of writing it is is expected to switch-on 10 December. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. The satellite is now transmitting during eclipses, although signals are weaker at those times. This indicates that there is still some capacity remaining in the battery. The on-board clock is now very stable. It gained eight seconds during November. This is comparable with its accuracy when the satellite was fully operational, when it gained approximately one minute per year. However, there is still an accumulated loss of 309 days, which has occurred during eclipses of the last few years. Operation during eclipses and stability of the on-board clock suggest that some part of the system may have recently failed 'open circuit' thus reducing the overall power drain of the system, and allowing more power to be available during eclipses. When analogue telemetry was last transmitted, an unexplained current drain was observed. This fault may have cleared. The Beacon frequencies are - VHF 145.826 MHz. AFSK FM ASCII Telemetry UHF 435.025 MHz. OFF S-band 2401.5 MHz. OFF Reception reports have been received from Gene WA4UKX, Horatio CX8AF, David G8OQW and Michael M0MPM/PA3BHE . Many thanks for those and to everyone who posted reports on the satellite status website. At the present time, while OSCAR-11 is operating in a predictable way, I no longer need direct reports by e-mail. However, could you continue to enter reports on the general satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites, and is of use to everyone. Reports around the expected times of switch-on and switch-off are of special interest. The URL is http://oscar.dcarr.org/index.php OSCAR-11 transmits on 145.826 MHz., set receiver to NBFM. The satellite has a characteristic sound, rather like raspy slow morse code, sending di di dah dah dah dah dah dah dah sent over a period of five seconds. If you are receiving a very weak signal, switch the receiver to CW or SSB. You should hear several sidebands around the carrier frequency and should be able to hear the characteristic 'morse code like' sound on at least one sideband. Please note that you need a clean noise-free signal to decode the signals, and your receiver must be set to NBFM mode, for a decoder to work. If you need to know what OSCAR-11 sounds like, there is an audio clip on my website www.g3cwv.co.uk/ which may be useful for identification and as a test signal for decoding. The current status of the satellite, is that all the analogue telemetry channels, 0 to 59 are zero, ie they have failed. The status channels 60 to 67 are still working. The real time clock is showing a large accumulated error, but is now incrementing accurately to within a few seconds per month. The day of the month has a bit stuck at 'one' so the day of the month may show an error of +40 days for some dates. The time display has switched into 12 hour mode. Unfortunately, there is no AM/PM indicator, since the time display format was designed for 24 hour mode. The spacecraft computer and active attitude control system have switched OFF, ie. the satellite' attitude is controlled only by the passive gravity boom gradient, and the satellite is free to spin at any speed. The watchdog timer operates on a 20 day cycle. The ON/OFF times have tended to be very consistent. The average of many observations have shown this to be 20.7 days, ie. 10.35 days ON followed by 10.35 days OFF. Listeners to OSCAR-11 may be interested in visiting my website. If you need to know what OSCAR-11 should sound like, there is a short audio clip for you to hear. The last telemetry received from the satellite is available for download. The website contains an archive of news telemetry data which is updated from time to time. It also contains details about using a soundcard or hardware demodulators for data capture. There is software for capturing data, and decoding ASCII telemetry. The URL is www.g3cwv.co.uk . If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT151 .CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace x by g3cwv) ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 31 October 2010 This report covers the period from 30 September to 31 October 2010. During this time the satellite has been heard from 09 to 19 October and from 30 October. At the time of writing it is transmitting and is expected to continue until 09 November. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. The satellite is now transmitting during eclipses, although signals are weaker at those times. This indicates that there is still some capacity remaining in the battery. The on-board clock is now very stable. It gained only ten seconds in 33 days. This is comparable with its accuracy when the satellite was fully operational, when it gained approximately one minute per year. However, there is still an accumulated loss of 309 days, which has occurred during eclipses of the last few years. Operation during eclipses and stability of the on-board clock suggest that some part of the system may have recently failed 'open circuit' thus reducing the overall power drain of the system, and allowing more power to be available during eclipses. There was an unexplained current drain observed when analogue telemetry was last transmitted. This fault might have cleared. The Beacon frequencies are - VHF 145.826 MHz. AFSK FM ASCII Telemetry UHF 435.025 MHz. OFF S-band 2401.5 MHz. OFF Reception reports have been received from Jeff N3QO, Rod CX2ABP and Ian KI4HLV/6Y5 (G4JMM) . Many thanks for those and to everyone who posted reports on the satellite status website. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites. Strongly recommended for future reports! Reports around the expected times of switch-on and switch-off are of special interest. The URL is http://oscar.dcarr.org/index.php OSCAR-11 transmits on 145.826 MHz., set receiver to NBFM. The satellite has a characteristic sound, rather like raspy slow morse code, sending di di dah dah dah dah dah dah dah sent over a period of five seconds. If you are receiving a very weak signal, switch the receiver to CW or SSB. You should hear several sidebands around the carrier frequency and should be able to hear the characteristic 'morse code like' sound on at least one sideband. Please note that you need a clean noise-free signal to decode the signals, and your receiver must be set to NBFM mode, for a decoder to work. If you need to know what OSCAR-11 sounds like, there is an audio clip on my website www.g3cwv.co.uk/ which may be useful for identification and as a test signal for decoding. The current status of the satellite, is that all the analogue telemetry channels, 0 to 59 are zero, ie they have failed. The status channels 60 to 67 are still working. The real time clock is showing a large accumulated error, but is now incrementing accurately to within a few seconds per month. The day of the month has a bit stuck at 'one' so the day of the month may show an error of +40 days for some dates. The time display has switched into 12 hour mode. Unfortunately, there is no AM/PM indicator, since the time display format was designed for 24 hour mode. The spacecraft computer and active attitude control system have switched OFF, ie. the satellite' attitude is controlled only by the passive gravity boom gradient, and the satellite is free to spin at any speed. The watchdog timer operates on a 20 day cycle. The ON/OFF times have tended to be very consistent. The average of many observations have shown this to be 20.7 days, ie. 10.3 day s ON followed by 10.4 days OFF. Listeners to OSCAR-11 may be interested in visiting my website. If you need to know what OSCAR-11 should sound like, there is a short audio clip for you to hear. The last telemetry received from the satellite is available for download. The website contains an archive of news telemetry data which is updated from time to time. It also contains details about using a soundcard or hardware demodulators for data capture. There is software for capturing data, and decoding ASCII telemetry. The URL is www.g3cwv.co.uk . If you place this bulletin on a terrestrial packet network, please use the bulletin identifier $BID:U2RPT150.CWV, to prevent duplication. 73 Clive G3CWV xx...@amsat.org (please replace x by g3cwv) ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 30 September 2010 This report covers the period from 30 March to 30 September 2010. During this time the satellite was silent until it was heard by JA0CAW on 29 August. Since then, it was heard until 08 September and from 18 to 29 September. Excellent signals have been reported from stations located around the world, and good copy obtained from decoded telemetry frames. There has been a significant change since the previous period of activity which ended in March 2010. The on-board clock is now very stable. It's gained only three seconds in 30 days. This is comparable with its accuracy when the satellite was fully operational. During its first 21 years it gained approximately one minute per year. However, there is still an accumulated loss of 309 days, which has occurred during eclipses of the last few years.! The other change is that it's now transmitting during eclipses, although signals are weaker at those times. This indicates that there is still some capacity remaining in the battery. These two changes suggest that some part of the system may have recently failed 'open circuit' thus reducing the overall power drain of the system, and allowing more power to be available during eclipses. There was an unexplained current drain observed when analogue telemetry was last transmitted. This fault might have cleared. Interestingly, the status telemetry shows that the Digital Store Readout experiment has switched off, since the satellite was previously heard in February. The satellite appears to be operating for ten days on, followed by ten days off, so it should start transmitting again around 09 October. The Beacon frequencies are - VHF 145.826 MHz. AFSK FM ASCII Telemetry UHF 435.025 MHz. OFF S-band 2401.5 MHz. OFF Reception reports have been received from Bernard FY1LE, Roland DG1EBR, Mike DK3WN, Tetsu JA0CAW, Adam SQ8MFC, MM0DNX, Tony VK3KKP/G8HIM, Martin DC1MAR, John M0BIC, Etienne F1GRR and Carlos KD6GRF. Many thanks to everyone. Many reports have also been added to the live satellite status page, on the website set up by David KD5QGR and Bob WB4APR. This is a very convenient and easy to use facility, which shows the current status of all the amateur satellites. Strongly recommended for future reports! The URL is http://oscar.dcarr.org/index.php For the benefit of new listeners, here is a short history of OSCAR-11. It was lauched in 1984, providing telemetry and other digital services for amateur radio and educational users. During its many years of operation it survived long periods of eclipses and continuous full sunlight. In 2002 the satellite reverted to its default mode of operation, controlled by the watchdog timer. In 2005 all the analogue telemetry channels failed. Solar eclipses also started to cause the watchdog timer cycle to reset, which switched off the satellite for approximately 15 days. In 2008 solar eclipses became a permanent feature of every orbit, causing the satellite to switch off for about 15 days, probably after only one orbit of transmission. Thus the satellite was not expected to be heard again for any continuous period until 2019, when there will be some eclipse free periods. However, the satellite started transmissions unexpectedly in November 2008. These continued until March, when it was followed by silence until until the recent period of activity. OSCAR-11 transmits on 145.826 MHz., set receiver to NBFM. The satellite has a characteristic sound, rather like raspy slow morse code, sending di di dah dah dah dah dah dah dah sent over a period of five seconds. If you are receiving a very weak signal, switch the receiver to CW or SSB. You should hear several sidebands around the carrier frequency and should be able to hear the characteristic 'morse code like' sound on at least one sideband. Please note that you need a clean noise-free signal to decode the signals, and your receiver must be set to NBFM mode, for a decoder to work. If you need to know what OSCAR-11 sounds like, there is an audio clip on my website www.g3cwv.co.uk/ which may be useful for identification and as a test signal for decoding. The current status of the satellite, is that all the analogue telemetry channels, 0 to 59 are zero, ie they have failed. The status channels 60 to 67 are still working. The real time clock is showing a large accumulated error, but is now incrementing accurately to within a few seconds per month. The day of the month has a bit stuck at 'one' so the day of the month may show an error of +40 days for some dates. The time display has switched into 12 hour mode. Unfortunately, there is no AM/PM indicator, since the time display format was designed for 24 hour mode. The spacecraft computer and active attitude control system have switched OFF, ie. the satellite' attitude is controlled only by the passive gravity boom gradient, and the satellite is free to spin at any speed. The watchdog timer now operates on a 20 day cycle. The
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 30 March 2010 OSCAR-11 achieved 26 years in orbit on 01 March! It was designed, built and launched within a period of six months, using commercially available 'off the shelf' components (COTS). Once again, congratulations to Professor Sir Martin Sweeting G3YJO, his team at the University of Surrey and groups of radio amateurs who also contributed to the project. Unfortunately, the satellite wasn't transmitting on its birthday, but was heard briefly, three days later. This report covers the period from 23 February to 30 March 2010. During this time the satellite was heard during three passes on 04 March. Good signals were received, and decoded. There was also an unconfirmed report that it was heard on 25 March. Due to eclipses, deterioration of the battery and other parts of the satellite, it's not possible to predict when the satellite will be heard in the coming months. It is likely that it may be heard occassionally, by stations tuning around the beacon frequency. The on-board clock was 263 days slow, when last heard on 04 March. The increasing error suggests that the clock may be stopping, when the satellite is in eclipse. Sometimes, the date counter also fails to increment. However, the retention of the date and time does suggest that a small amount of power may be still available during eclipses. The Beacon frequencies are - VHF 145.826 MHz. AFSK FM ASCII Telemetry UHF 435.025 MHz. OFF S-band 2401.5 MHz. OFF - RECEPTION REPORTS REQUESTED! Please send reception reports to xx...@amsat.org (replace x by g3cwv) or post to amsat-bb. If you have a file, please do not send it but let me know that it is available. You may also like to add your reception report to the live satellite status page, on the website set up by David KD5QGR and Bob WB4APR. The URL is http://oscar.dcarr.org/index.php The satellite transmits on 145.826 MHz., set receiver to NBFM. OSCAR-11 has a characteristic sound, rather like raspy slow morse code, sending di di dah dah dah dah dah dah dah sent over a period of five seconds. If you are receiving a very weak signal, switch the receiver to CW or SSB. You should hear several sidebands around the carrier frequency and should be able to hear the characteristic 'morse code like' sound on at least one sideband. Please note that you need a clean noise-free signal to decode the signals, and your receiver must be set to NBFM mode, for a decoder to work. If you need to know what OSCAR-11 sounds like, there is an audio clip on my website www.g3cwv.co.uk/ which may be useful for identification and as a test signal for decoding. - The satellite is now subject to eclipses during every orbit. Long term predictions indicate that eclipses will occur until 2019, when there will be some eclipse free periods until 2023. However these very long term predictions should be regarded with caution, as large tracking errors can accumulate over long periods of time. When eclipses started around 2005 the watchdog timer often switched the transmitter off before the ten day on period had finished, during parts of the eclipse cycle. When eclipses became a permanent feature of all orbits, after April 2008, the transmitter switched off within a single orbit, thus the satellite was effectively non operational. The satellite unexpectedly started regular transmissions in November 2009. Although there was a small variation in the length of eclipses, this wasn't enough to explain why the satellite started regular transmissions. It is possible that a fault developed, which prevented the watchdog timer resetting when the power supply fails, and now the watchdog timer settings are no longer retained during eclipses. The transmitter switches off during eclipses, and the real time clock stops during most of the eclipse. When analogue telemetry was last received, in 2005, it showed that one of the solar arrays had failed, and there was a large unexplained current drain on the main 14 volt bus. After 26 years in orbit the battery has undergone over 100,000 partial charge/discharge cycles, and observations indicate that it cannot power the satellite during eclipses. The current status of the satellite, is that all the analogue telemetry channels, 0 to 59 are zero, ie they have failed. The status channels 60 to 67 are still working. The real time clock is showing a large accumulated error, although during ten minute passes the clock increments correctly to within one second. The day of the month has a bit stuck at 'one' so the day of the month may show an error of +40 days for some dates. The time display has switched into 12 hour mode. Unfortunately, there is no AM/PM indicator, since the time display format was designed for 24 hour mode. The spacecraft computer and active attitude control system have switched OFF, ie. the satellite' attitude is controlled only by the
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 24 February 2010 This report covers the period from 11 January to 23 February 2010. During this time the satellite was heard from 21 to 31 January and 11 to 24February. Good signals were received, and decoded. Signals have been very strong, although frequent changes in polarisation have been observed. The satellite has only transmitted when in sunlight. The next transmissions are expected around 04 March 2010. The on-board clock was 260 days slow, when last heard on 21 February. The increasing error suggests that the clock may be stopping, when the satellite is in eclipse. Sometimes, the date counter also fails to increment. Reception reports have been received from stations located all over the world including Peter Zl3TC, Jon 2M0IBO, Mike DK3WN, Adrian LU1CBG, Robert VE2PRS, Ken GW1FKY and Alan ZL2BX. Many thanks to everyone who sent email reports, posted to AMSAT-BB or updated the KD5QGR/WB4APR satellite status website. The Beacon frequencies are - VHF 145.826 MHz. AFSK FM ASCII Telemetry UHF 435.025 MHz. OFF S-band 2401.5 MHz. OFF - RECEPTION REPORTS REQUESTED! I am particularly interested in reports of reception during the hours 23:00 to 06:00 and 12:00 to 17:00 UTC, especially near expected switch on or off dates. Please send reception reports to xx...@amsat.org (replace x by g3cwv) or post to amsat-bb. If you have a file, please do not send it but let me know what is available. You may also like to add your reception report to the live satellite status page, on the website set up by David KD5QGR and Bob WB4APR. The URL is http://oscar.dcarr.org/index.php The satellite transmits on 145.826 MHz., set receiver to NBFM. OSCAR-11 has a characteristic sound, rather like raspy slow morse code, sending di di dah dah dah dah dah dah dah sent over five seconds. If you are receiving a very weak signal, switch the receiver to CW or SSB. You should hear several sidebands around the carrier frequency, and should be able to hear the characteristic 'morse code like' sound on at least one sideband. Please note that you need a clean noise free signal to decode the signals. There is an audio clip on my website www.g3cwv.co.uk which may be useful for identification and as test signal for decoding. - The satellite is now subject to eclipses during every orbit. Long term predictions indicate that eclipses will occur until 2019, when there will be some eclipse free periods until 2023. However these very long term predictions should be regarded with caution, as large tracking errors can accumulate over long periods of time. When eclipses started around 2005 the watchdog timer often switched the transmitter off before the ten day on period had finished, during parts of the eclipse cycle. When eclipses became a permanent feature of all orbits, after April 2008, the transmitter switched off within a single orbit, thus the satellite was effectively non operational. The satellite unexpectedly started regular transmissions in November 2009. It is possible that a fault has developed, which prevents the watchdog timer resetting when the power supply fails. The transmitter switches off during eclipses, and the real time clock stops during most of the eclipse. When analogue telemetry was last received, in 2005, it showed that one of the solar arrays had failed, and there was a large unexplained current drain on the main 14 volt bus. After 25 years in orbit the battery has undergone over 100,000 partial charge/discharge cycles, and observations indicate that it cannot power the satellite during eclipses. The current status of the satellite, is that all the analogue telemetry channels, 0 to 59 are zero, ie they have failed. The status channels 60 to 67 are still working. The real time clock is showing a large accumulated error, although during ten minute passes the clock increments correctly to within one second. The day of the month has a bit stuck at 'one' so the day of the month may show an error of +40 days for some dates. The time display has switched into 12 hour mode. Unfortunately, there is no AM/PM indicator, since the time display format was designed for 24 hour mode. The spacecraft computer and active attitude control system have switched OFF, ie. the satellite' attitude is controlled only by the passive gravity boom gradient, and the satellite is free to spin at any speed. The watchdog timer now operates on a 20 day cycle. The ON/OFF times have tended to be very consistent. The average of many observations show this to be 20.7 days, ie. 10.3 day s ON followed by 10.4 days OFF. Listeners to OSCAR-11 may be interested in visiting my website. If you need to know what OSCAR-11 should sound like, there is a short audio clip for you to hear. The last telemetry received from the satellite is available for download. The website contains an archive of news
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 14 January 2010 This report covers the period from 30 November 2009 to 14 January 2010. During this time the satellite was heard briefly on 10 11 December and then from 31 December until 10 January. Good signals were received, and decoded. Sometimes signals have been very strong, although frequent changes in polarisation have been observed. The satellite was not heard during solar eclipses, which now occur during the afternoon and evening passes over the UK. The last two 'off' periods have lasted 14 and 19 days respectively, suggesting that the watchdog timer has been reset. However, the last transmission period lasted for the full ten days, so it is possible that transmissions may resume after ten days of silence, ie. around 20 January. However, please note that the satellite's behaviour is now very unpredictable, and until a pattern of operation is established, it is impossible to predict what will happen next, with any certainty. The telemetry is unchanged from the 2008 downloads. The on-board clock is now 252 days slow. When last received in 2008 it was 83 days slow. The increasing error suggests that the clock may be stopping, when the satellite is in eclipse. During the last transmission period the date failed to increment on one occasion, from 29 to 30 May. - RECEPTION REPORTS REQUESTED! Please send reception reports to xx...@amsat.org (replace x by g3cwv) or post to amsat-bb. If you have a file, please discuss it with me, before sending it! You may also like to add your reception report to the live satellite status page, on the website set up by David KD5QGR and Bob WB4APR. The URL is http://oscar.dcarr.org/index.php The satellite transmits on 145.826 MHz., set receiver to NBFM. OSCAR-11 has a characteristic sound, rather like raspy slow morse code, sending di di dah dah dah dah dah dah dah sent over five seconds. If you are receiving a very weak signal, switch the receiver to CW or SSB. You should hear several sidebands around the carrier frequency, should be able to hear the characteristic 'morse code like' sound usually on at least two of the sidebands. Please note that you need a clean noise free signal to decode the signals. There is an audio clip on my website www.g3cwv.co,uk which may be useful for identification and as test signal for decoding. - Reception reports have been received from Peter ZL3TC, Mike DK3WN, Jon 2M0IBO and Detlef DJ3AK. Many thanks for those. The Beacon frequencies are - VHF 145.826 MHz. AFSK FM ASCII Telemetry UHF 435.025 MHz. OFF S-band 2401.5 MHz. OFF The satellite is now subject to eclipses during every orbit. Long term predictions indicate that eclipses will occur until 2019, when there will be some eclipse free periods until 2023. However these very long term predictions should be regarded with caution, as large tracking errors can accumulate over long periods of time. When analogue telemetry was last received in March 2005, it showed that one of the solar arrays had failed, and there was a large unexplained current drain on the main 14 volt bus. After 25 years in orbit the battery has undergone over 100,000 partial charge/discharge cycles, and observations suggest that it cannot power the satellite during eclipses lasting more than about ten minutes, or sometimes even during periods of poor solar attitude. Study of the satellite's behaviour prior to 2008 suggested that its battery would not sustain operation during solar eclipses, and the watchdog timer would switch the satellite OFF after less than an orbit. Eclipses are now occur during every orbit and will continue for many years. In practice this meant that OSCAR-11 would only be heard occasionally by stations monitoring the frequency while listening for other satellites. The satellite unexpectedly started sustained transmissions during November 2009, suggesting that there may have been a failure causing reduced drain on the power supplies or a change in the watchdog timer characteristics. The current status of the satellite, is that all the analogue telemetry channels, 0 to 59 are zero, ie they have failed. The status channels 60 to 67 are still working. The real time clock is showing a large accumulated error, although over short periods timekeeping is accurate to a few seconds per month. The day of the month has a bit stuck at 'one' so the day of the month may show an error of +40 days for some dates. The time display has switched into 12 hour mode. Unfortunately, there is no AM/PM indicator, since the time display format was designed for 24 hour mode. The spacecraft computer and active attitude control system have switched OFF, ie. the satellite' attitude is controlled only by the passive gravity boom gradient, and the satellite is free to spin at any speed. The watchdog timer now operates on a 20 day cycle. The ON/OFF times have tended to be
[amsat-bb] OSCAR-11 Report
OSCAR-11 REPORT 30 November 2009 This report covers the period from 21 April 2008 to 30 November 2009. The satellite unexpectedly resumed transmissions recently. It was first heard by Keith N4ZQ on 19 November 2009 and transmissions continued until it switched OFF on 27 November. It was last heard by Tetsu JA0CAW at 23:59 UTC 26 November 2009. Previously, it was last heard by Peter ZL3TC on 23 April 2008, on a single pass. Study of the satellite's behaviour had suggested that its battery would not sustain operation during solar eclipses, and the watchdog timer would switch the satellite OFF after less than an orbit. Eclipses are now occur during every orbit and will continue for many years. In practice this meant that OSCAR-11 would only be heard occasionally by stations monitoring the frequency while listening for other satellites. During this period of inactivity the satellite achieved 25 years in orbit on 01 March 2009. Congratualtions to Professor Sir Martin Sweeting, his team at the University of Surrey and participating amateur radio groups, for this fine achievment. Good signals have been received by stations located all over the world during this recent period of activity and telemetry has been decoded successfully. However, the satellite has only transmitted when in sunlight. I have been overwhelmed by the number of reports received, too many to list individually! Many thanks to everyone who sent email reports or posted to AMSAT-BB. The telemetry is unchanged from the 2008 downloads. The on-board clock is now 241 days slow. When last received in 2008 it was 83 days slow. The increasing error suggests that the clock may be stopping, when the satellite is in eclipse. The exact date when the satellite started transmitting is not known, so if the watchdog timer was reset, the next transmissions might start around 16 December, however if the timer went through its full operating cycle, transmissions could resume around 06 December. The Beacon frequencies are - VHF 145.826 MHz. AFSK FM ASCII Telemetry UHF 435.025 MHz. OFF S-band 2401.5 MHz. OFF The satellite is now subject to eclipses during every orbit. Long term predictions indicate that eclipses will occur until 2019, when there will be some eclipse free periods until 2023. However these very long term predictions should be regarded with caution, as large tracking errors can accumulate over long periods of time. When telemetry was last received it showed that one of the solar arrays had failed, and there was a large unexplained current drain on the main 14 volt bus. After 25 years in orbit the battery has undergone over 100,000 partial charge/discharge cycles, and observations suggest that it cannot power the satellite during eclipses lasting more than about ten minutes, or sometimes even during periods of poor solar attitude. - RECEPTION REPORTS REQUESTED! Please send reception reports to xx...@amsat.org (replace x by g3cwv) or post to amsat-bb. If you have a file, please let me know what you have, before sending it! The satellite transmits on 145.826 MHz., set receiver to NBFM. OSCAR-11 has a characteristic sound, rather like raspy slow morse code, sending di di dah dah dah dah dah dah dah sent over five seconds. If you are receiving a very weak signal, switch the receiver to CW or SSB. You should hear several sidebands around the carrier frequency, should be able to hear the characteristic 'morse code like' sound on at least one sideband. Please note that you need a clean noise free signal to decode the signals. There is an audio clip on my OLD website www.users.zetnet.co.uk/clivew/ which may be useful for identification and as test signal for decoding. - The current status of the satellite, is that all the analogue telemetry channels, 0 to 59 are zero, ie they have failed. The status channels 60 to 67 are still working. The real time clock is showing a large accumulated error, although over short periods timekeeping is accurate to a few seconds per month. When last heard the clock was 241 days slow. The day of the month has a bit stuck at 'one' so the day of the month may show an error of +40 days for some dates. The time display has switched into 12 hour mode. Unfortunately, there is no AM/PM indicator, since the time display format was designed for 24 hour mode. The spacecraft computer and active attitude control system have switched OFF, ie. the satellite' attitude is controlled only by the passive gravity boom gradient, and the satellite is free to spin at any speed. The watchdog timer now operates on a 20 day cycle. The ON/OFF times have tended to be very consistent. The average of many observations show this to be 20.7 days, ie. 10.3 days ON followed by 10.4 days OFF. However, poor solar attitude may result may result in a low 14 volt line supply, which may cause the
