[amsat-bb] Re: AO-7 is not OK
Hi Piraja and Mike Today during revolution 62062 over Europe AO-7 was in Mode-A and I did a nice and long QSO with SV1EEK Signal where strong but the transponder was FM-ing like in Mode-B and this is unusual in Mode-A Probably a poor solar panels illumination ? 73" de i8CVS Domenico - Original Message - From: "Mike Rupprecht" To: "'ps8rf Piraja'" ; Sent: Wednesday, April 14, 2010 6:25 PM Subject: [amsat-bb] Re: AO-7 is not OK Hi Piraja, Yes, I made similar observations. If the CW is active on 70cm you can hear sometimes a very strong deviation in frequency. The CW beacon partly not decodable. I agree with you it could be an effect by low batteries or due heavy usage. See some graphs here: http://www.dk3wn.info/p/?cat=21 73, Mike DK3WN -Ursprüngliche Nachricht- Von: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] Im Auftrag von ps8rf Piraja Gesendet: Mittwoch, 14. April 2010 13:22 An: amsat-bb@amsat.org Betreff: [amsat-bb] AO-7 is not OK Some days we are seeing very strange behavior in the AO-7. In some orbits can only hear the feedback on the downlink when the satellite is approaching my station at about 30 degrees elevation, before is impossible to hear any signal via AO-7. Using two pre-amplifier, one in the TS 2000x and the other with 0.6 noise with 20 dB gain. During the orbits we transmiting power with of 30 watts. The satellite does not respond. Tried with 15 watts It was then that we hear at certain points on the downlink audio too low. Its best performance is when the satellite is almost 90 degrees from my station. Yet it seems that the satellite is asking for help. This seems the batteries are not getting enough loads. Or maybe it's excessive use of power by the users of the satellite. Maybe it's time for the users of AO-7 rethink the best ways to keep QSO through it, such as the use of LOW POWER so that over time the satellite is stabilized. "Long live the AO-7" 73' Piraja, PS8RF The Amateur Radio is supportive and helpful in any circumstance. _ Você sabia que seu navegador te ajuda a ficar longe de vírus? Leia mais sobre isso. http://www.microsoft.com/brasil/windows/internet-explorer/?WT.mc_id=1500 ___ 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 ___ 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 ___ 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] Re: AO-7 is not OK
Pete, Come on now, we all treat her like a lady, don't we? Always a few, Pete, that never listen to suggestions...Hope all is well and your weather site looks great. Hope you're planning a few hamfest this year for AMSAT. Been to quite a few already and hopefully we keep spreading the words... 73, Dee, NB2F -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Peter Portanova Sent: Wednesday, April 14, 2010 2:21 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: AO-7 is not OK Tim, As usual, very informative information on "The Grand Land", AO-7! Tim you remind me of only a few professional athletes who respect the game, know it's history and play it "correctly". Well, AO-7 is like an aging athlete, don't put to much pressure on her or ask her to do to much. I'm disappointed in a few operators who don't understand or care what too much power can do to a linear satellites passband, if this was HF everybody would be doing it, thank you for teaching all of us Tim. 73's Pete WB2OQQ www.massapequanyweather.com ___ 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 ___ 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] Re: AO-7 is not OK
Hello, Correction, "The Grand Lady" AO-7. 73's Pete WB2OQQ www.massapequanyweather.com ___ 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] Re: AO-7 is not OK
Tim, As usual, very informative information on "The Grand Land", AO-7! Tim you remind me of only a few professional athletes who respect the game, know it's history and play it "correctly". Well, AO-7 is like an aging athlete, don't put to much pressure on her or ask her to do to much. I'm disappointed in a few operators who don't understand or care what too much power can do to a linear satellites passband, if this was HF everybody would be doing it, thank you for teaching all of us Tim. 73's Pete WB2OQQ www.massapequanyweather.com ___ 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] Re: AO-7 is not OK
> > > Hi Piraja, > > Yes, I made similar observations. If the CW is active on 70cm you can hear > sometimes a very strong deviation in frequency. > The CW beacon partly not decodable. I agree with you it could be an effect > by low batteries or due heavy usage. > See some graphs here: http://www.dk3wn.info/p/?cat=21 > > 73, Mike > DK3WN > Hi gang! There is no battery left in AO-7. All the current is generated by solar panels and the only "power buffer" is the capacitors in the regulator board. This may cause the voltage drop that also affects to output power and shifts oscillators. The solar panels are quite old too... 73, Jari oh3uw ___ 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] Re: AO-7 is not OK
Great Reply Tim, I try to tell the ops on AO7 to watch there input power. This old lady just can't handle us old men pumping the high power into her. By the way, I had some very distorted signal the other morning and was so afraid she was damaged. Best 73's AO7 ops, See ya on the bird! Dave, kn4ok Mike, Piraja and all, Please take a moment to visit the page on the AO-7 Web site that includes an ssay from AO-7 Project Manager Jan King, W3GEY. You will find that essay here: ttp://www.planetemily.com/ao7/history.php?PHPSESSID=5cc1e3be993405e687967faffcac4407 According to Jan, AO-7 no longer uses batteries in its current condition. It is owered completely by the solar array. He explains fully what he believes to ave happened. Here are some excepts for the full essay Jan wrote, which appears n the page I provided the link to (NOTE - scroll down toward the borrom of the age to find Jan's report): "I am certain what has happened (and I know why): The battery did fail short. irtually all of the cells failed in a shorted mode eventually. This shorted ondition placed a shunt across the solar arrays and prevented current from oing to the satellite loads (i.e. the transponders, in particular). Some time efore G3IOR reported hearing the spacecraft again the short on one of the cells 1 out of 10) failed a second time. This time, it went from short to "open." hen it went open this released the shunt that was pulling the array voltage own and allowed the current to pass to the satellite loads. Since there is no attery at all now (because one cell went open), when AO-7 goes into eclipse ith each orbit, the satellite has no power to operate and shuts down in the ark." lso: People should realize that the solar arrays are old and they don't put out more han a few watts now. That's the only power available to run the ransponders.So, if they uplink too much power it will just cause the ransmitter to sort of 'cave in.' The voltage on the satellite bus begins to sag adly when a heavy demand is placed on the transponder (by a large uplinking ignal) since there is nothing there to regulate it and then the oscillators in he receiver and transmitter chain start changing frequency. People call this FMing' and that is what is going on." an's entire essay is fascinating. The primary reason I consider AO-7 the flagship of the amateur satellite fleet s her amazing story and legacy. I consider myself blessed and fortunate to have n opportunity to work the "Grand Old Girl" now, more than 25 years after she eached orbit. Even on her bad days - and today appears to be one, as I write his - I am able to clearly copy my CW signal on the downlink from about 20 egrees elevation running only 5 watts out of a Yaesu FT-817 from my handheld lk dual-band yagi - and working from inside my home on the second floor, my plink signal shooting through the second-floor ceiling and roof. I believe she poils us on her good days with the ability to enable contacts that span oceans nd continents - even with a station like mine. am grateful for every orbit during which I am able to hear such an amazing iece of amateur-radio hardware still working as hard as she can. 3 to all, im - N3TL ___ rom: Mike Rupprecht o: ps8rf Piraja ; amsat-bb@amsat.org ent: Wed, April 14, 2010 12:25:03 PM ubject: [amsat-bb] Re: AO-7 is not OK Hi Piraja, Yes, I made similar observations. If the CW is active on 70cm you can hear ometimes a very strong deviation in frequency. he CW beacon partly not decodable. I agree with you it could be an effect y low batteries or due heavy usage. ee some graphs here: http://www.dk3wn.info/p/?cat=21 73, Mike K3WN Ursprüngliche Nachricht- on: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] Im uftrag von ps8rf Piraja esendet: Mittwoch, 14. April 2010 13:22 n: amsat-bb@amsat.org etreff: [amsat-bb] AO-7 is not OK ome days we are seeing very strange behavior in the AO-7. In some orbits an only hear the feedback on the downlink when the satellite is approaching y station at about 30 degrees elevation, before is impossible to hear any ignal via AO-7. Using two pre-amplifier, one in the TS 2000x and the other ith 0.6 noise with 20 dB gain. During the orbits we transmiting power with f 30 watts. The satellite does not respond. Tried with 15 watts It was hen that we hear at certain points on the downlink audio too low. Its best erformance is when the satellite is almost 90 degrees from my station. et it seems that the satellite is asking for help. This seems the batteries are not getting enough loads. Or maybe it's xcessive use of power by the users of the satellite. Maybe it's time for the users of AO-7 rethink the best ways to keep QSO hrough it, such as the use of LOW POWER so that over time the satellite is tabilized. "Long l
[amsat-bb] Re: AO-7 is not OK
Hi Piraja and Mike As far I know actually the batteries of AO-7 are an open circuit and this is why the satellite started to work again. Before for many years AO-7 was silent because the batteries where in a short circuit condition. AO-7 is actually working only when the solar panels are illuminated and so the panels power is managed only by the BCR (Battery Charge Regulator) but the batteries are out of service. Yesterday April 13 during revolution 62037 AO-7 was in Mode-A over Europe and signals where strong and clear without the well know FM-ing normally affecting the Mode-B transponder. 73" de i8CVS Domenico - Original Message - From: "Mike Rupprecht" To: "'ps8rf Piraja'" ; Sent: Wednesday, April 14, 2010 6:25 PM Subject: [amsat-bb] Re: AO-7 is not OK Hi Piraja, Yes, I made similar observations. If the CW is active on 70cm you can hear sometimes a very strong deviation in frequency. The CW beacon partly not decodable. I agree with you it could be an effect by low batteries or due heavy usage. See some graphs here: http://www.dk3wn.info/p/?cat=21 73, Mike DK3WN -Ursprüngliche Nachricht- Von: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] Im Auftrag von ps8rf Piraja Gesendet: Mittwoch, 14. April 2010 13:22 An: amsat-bb@amsat.org Betreff: [amsat-bb] AO-7 is not OK Some days we are seeing very strange behavior in the AO-7. In some orbits can only hear the feedback on the downlink when the satellite is approaching my station at about 30 degrees elevation, before is impossible to hear any signal via AO-7. Using two pre-amplifier, one in the TS 2000x and the other with 0.6 noise with 20 dB gain. During the orbits we transmiting power with of 30 watts. The satellite does not respond. Tried with 15 watts It was then that we hear at certain points on the downlink audio too low. Its best performance is when the satellite is almost 90 degrees from my station. Yet it seems that the satellite is asking for help. This seems the batteries are not getting enough loads. Or maybe it's excessive use of power by the users of the satellite. Maybe it's time for the users of AO-7 rethink the best ways to keep QSO through it, such as the use of LOW POWER so that over time the satellite is stabilized. "Long live the AO-7" 73' Piraja, PS8RF The Amateur Radio is supportive and helpful in any circumstance. _ Você sabia que seu navegador te ajuda a ficar longe de vírus? Leia mais sobre isso. http://www.microsoft.com/brasil/windows/internet-explorer/?WT.mc_id=1500 ___ 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 ___ 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 ___ 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] Re: AO-7 is not OK
Mike, Piraja and all, Please take a moment to visit the page on the AO-7 Web site that includes an essay from AO-7 Project Manager Jan King, W3GEY. You will find that essay here: http://www.planetemily.com/ao7/history.php?PHPSESSID=5cc1e3be993405e687967faffcac4407 According to Jan, AO-7 no longer uses batteries in its current condition. It is powered completely by the solar array. He explains fully what he believes to have happened. Here are some excepts for the full essay Jan wrote, which appears on the page I provided the link to (NOTE - scroll down toward the borrom of the page to find Jan's report): "I am certain what has happened (and I know why): The battery did fail short. Virtually all of the cells failed in a shorted mode eventually. This shorted condition placed a shunt across the solar arrays and prevented current from going to the satellite loads (i.e. the transponders, in particular). Some time before G3IOR reported hearing the spacecraft again the short on one of the cells (1 out of 10) failed a second time. This time, it went from short to "open." When it went open this released the shunt that was pulling the array voltage down and allowed the current to pass to the satellite loads. Since there is no battery at all now (because one cell went open), when AO-7 goes into eclipse with each orbit, the satellite has no power to operate and shuts down in the dark." Also: "People should realize that the solar arrays are old and they don't put out more than a few watts now. That's the only power available to run the transponders.So, if they uplink too much power it will just cause the transmitter to sort of 'cave in.' The voltage on the satellite bus begins to sag badly when a heavy demand is placed on the transponder (by a large uplinking signal) since there is nothing there to regulate it and then the oscillators in the receiver and transmitter chain start changing frequency. People call this 'FMing' and that is what is going on." Jan's entire essay is fascinating. The primary reason I consider AO-7 the flagship of the amateur satellite fleet is her amazing story and legacy. I consider myself blessed and fortunate to have an opportunity to work the "Grand Old Girl" now, more than 25 years after she reached orbit. Even on her bad days - and today appears to be one, as I write this - I am able to clearly copy my CW signal on the downlink from about 20 degrees elevation running only 5 watts out of a Yaesu FT-817 from my handheld Elk dual-band yagi - and working from inside my home on the second floor, my uplink signal shooting through the second-floor ceiling and roof. I believe she spoils us on her good days with the ability to enable contacts that span oceans and continents - even with a station like mine. I am grateful for every orbit during which I am able to hear such an amazing piece of amateur-radio hardware still working as hard as she can. 73 to all, Tim - N3TL From: Mike Rupprecht To: ps8rf Piraja ; amsat-bb@amsat.org Sent: Wed, April 14, 2010 12:25:03 PM Subject: [amsat-bb] Re: AO-7 is not OK Hi Piraja, Yes, I made similar observations. If the CW is active on 70cm you can hear sometimes a very strong deviation in frequency. The CW beacon partly not decodable. I agree with you it could be an effect by low batteries or due heavy usage. See some graphs here: http://www.dk3wn.info/p/?cat=21 73, Mike DK3WN -Ursprüngliche Nachricht- Von: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] Im Auftrag von ps8rf Piraja Gesendet: Mittwoch, 14. April 2010 13:22 An: amsat-bb@amsat.org Betreff: [amsat-bb] AO-7 is not OK Some days we are seeing very strange behavior in the AO-7. In some orbits can only hear the feedback on the downlink when the satellite is approaching my station at about 30 degrees elevation, before is impossible to hear any signal via AO-7. Using two pre-amplifier, one in the TS 2000x and the other with 0.6 noise with 20 dB gain. During the orbits we transmiting power with of 30 watts. The satellite does not respond. Tried with 15 watts It was then that we hear at certain points on the downlink audio too low. Its best performance is when the satellite is almost 90 degrees from my station. Yet it seems that the satellite is asking for help. This seems the batteries are not getting enough loads. Or maybe it's excessive use of power by the users of the satellite. Maybe it's time for the users of AO-7 rethink the best ways to keep QSO through it, such as the use of LOW POWER so that over time the satellite is stabilized. "Long live the AO-7" 73' Piraja, PS8RF The Amateur Radio is supportive and helpful in any circumstance. _ Você sabia que seu navegador te ajuda a ficar
[amsat-bb] Re: AO-7 is not OK
Hi Piraja, Yes, I made similar observations. If the CW is active on 70cm you can hear sometimes a very strong deviation in frequency. The CW beacon partly not decodable. I agree with you it could be an effect by low batteries or due heavy usage. See some graphs here: http://www.dk3wn.info/p/?cat=21 73, Mike DK3WN -Ursprüngliche Nachricht- Von: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] Im Auftrag von ps8rf Piraja Gesendet: Mittwoch, 14. April 2010 13:22 An: amsat-bb@amsat.org Betreff: [amsat-bb] AO-7 is not OK Some days we are seeing very strange behavior in the AO-7. In some orbits can only hear the feedback on the downlink when the satellite is approaching my station at about 30 degrees elevation, before is impossible to hear any signal via AO-7. Using two pre-amplifier, one in the TS 2000x and the other with 0.6 noise with 20 dB gain. During the orbits we transmiting power with of 30 watts. The satellite does not respond. Tried with 15 watts It was then that we hear at certain points on the downlink audio too low. Its best performance is when the satellite is almost 90 degrees from my station. Yet it seems that the satellite is asking for help. This seems the batteries are not getting enough loads. Or maybe it's excessive use of power by the users of the satellite. Maybe it's time for the users of AO-7 rethink the best ways to keep QSO through it, such as the use of LOW POWER so that over time the satellite is stabilized. "Long live the AO-7" 73' Piraja, PS8RF The Amateur Radio is supportive and helpful in any circumstance. _ Você sabia que seu navegador te ajuda a ficar longe de vírus? Leia mais sobre isso. http://www.microsoft.com/brasil/windows/internet-explorer/?WT.mc_id=1500 ___ 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 ___ 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
