Hi, my grandmother built that satellite, along with Jan King and others. her name was Marie Marr. I have pictures and articles about the other Oscars she helped create. My grandma was a ham radio enthusiast and could build them with everyday objects and tools. She lived in Greenbelt Maryland and was commissioned by NASA to build piggy back satellites. Btw in the picture was my grandmother. Thanks for sharing your video with us.
She was amazing! When researching for the video she stood out and was in so many of the photos! I knew who she was before I knew who Jan was lol. I posted on her obituary because she was so inspiring to me. Thank you for sharing your story as well, she will always be a badass! :)
@@retrorockets6465 when I was younger, she rode a Harley Davidson. She was very progressive. The only reason she didn't go further in NASA was because she lacked a college degree. When she built Oscar 7 she was a grandmother already, so college was out.
Since the satellite is passively stabilized magnetically, the spin wasn't for extra stabilization, but for thermal control. You need the satellite to rotate constantly so sun exposure doesn't bake one side while the other freezes.
True, I'll add that as a correction as you're not wrong! Although I will point out that with the Photon prop, it's primary use is just to keep it's spin rate from decaying, can't control thermals if you stop spinnin' :)
Look at it this way, magnets are only to keep earth orientation up until the poles, but the spin rate is still needed and is all controlled by photon prop and the hysteresis bars. I will reiterate though that you are right that it handles thermal control as well, and I added a correction mentioning ya!
Thank you so much for taking the time to put this video together, it is truly fascinating. I did work it and oscar 8 back in 1979 or 80 and it was considered an old bird even then. I have not looked for it in many years but perhaps I should? Again Thank You
It was a thrill to communicate long-distance as far away as Europe and Venezuela through Oscar 7 using a simple hand-pointed antenna inside my apartment, along with some cobbled-together converters, radios, and stuff lying on the floor, plus a homemade orbit plotting device that showed where to point the antenna. Great fun. Many thanks to those who created Oscar 7.
Great to hear that it is still working! My first contact via OSCAR 7 (I'm in the UK) was orbit 21, a few hours after launch, with a ham in the Netherlands (using CW)..
"Aircraft grade aluminum" is marketing speak and means nothing. While far from exhaustive I have spent years at work looking over material specifications and I never once encountered the term "aircraft grade" in reference to anything by any standards organization. Also most "aircraft grade aluminum" is 6061 which is a good alloy but is as close to a generic alloy as you can get, you really should point at an airplane or satelite and say "this thing is made of lawn chair grade 6061 aluminum!"
I started satellites in the fall of 2019 and have worked A07 many times on the 10M down-link. Both CW and SSB. Always a challenge but it works. I never knew when it died or came back to life. Great video. Well done. VE4MM
I was operating OSCAR 7’s Mode U/V transponder earlier this week; occasionally the quality of the repeated SSB signals sounds slightly distorted, a condition called “FMing”. This occurs when the power drain from the transponder approaches the limits of what the solar cells can supply; it affects the frequency stability of the transponder’s oscillators, causing them to vary in frequency in time with some of the strongest SSB voice peaks. The way to avoid or at least minimize this effect is for hams to voluntarily limit the power of their uplink transmissions. 😊 Tom WA1LBK
*PLEASE* consider doing a series on more of these derelict birds! This video was my first exposure to your channel, and 30 seconds later I subbed. To say that you've got potential on this platform would be a massive understatement.
What a great video. Subscribed and thumbs up. This is some history that I didn't know. Amazing that a satellite constructed so long ago could still be functional. As a ham I really enjoyed this. It kinda makes me wonder how long the lil satellite that could will make it?? This makes me wanna pull out some gear and give it a try!!
I read a code book for land based wire morse telegraphers once. Theres a lot you can do with it using combinations of letters. It was like data compression but UK 1870ish style. Exactly what its date was I couldn't say but it had codes for sentances that talked of departure and arrival dates and times, ships trains coal lamp oil cargo and horses etc and never once mentioned cars or radio. One synchronized all the clocks on a railway network and thus every single clock and pocket watch in an entire town or village. I imagine someone somewhere in London had a telescope locked on Big Ben.
That's wild, telegraph goes wayy back! And yes! I remember hearing about how before that tech came along, they would use air lines and air pulses from a main clock and it was a pain to deal with haha
The telescopes were aimed at a large leather covered wooden ball in a tower at the Greenwich Observatory that was visible from the Thames docs where all the ships navigators would look to reset their chronographs at noon every day when it fell. Accurate chips chronometers were the tool that allowed for accurate East-West ocean navigation and mapping using the stars and sun to determine latitude.
I restore ARC RT 328 radios, when I can. One key to lasting gadgets is shrewdness and quality of components. Keep their count low, and don't design yourself into a box. Components, like crystals, that don't last must last. Design for them to last for as long as possible. Keep things super light.
Always a fan of AO7, quite a lot of years ago, my friend John, LA2QAA (SK) and myself GM1SXX noticed a strange anomaly with AO7 while we were decoding what we liked to call'watery telemetry'... weak and warbling . Despite being in permanent sunlight, the mode switching timer was not operating accurately, which we found very strange given it was an xtal controlled timer. After exchanging some emails back and forth with Jan King W3GEY, we found out why. Due to time constraints, they couldn't source a suitable crystal for the timer to meet the launch date , so instead they concocted an RC timer to do the job. Of course such timers drift like the driven snow. It was a very interesting time in my ham journey.
Good question! Probably (just assuming) because most craft have power based memory so they'll lose programing once they lose solar power when going into eclipse. AO 7 is just that old school to where it can keep rebooting even if all power is lost. Just my guess though lol
UoSat Oscar 11 is still orbiting and transmitting telemetry too. Launched March 1984, designed and built by staff and students at the University of Surrey, under Martin Sweeting, here in the UK. Many of which went on to form Surrey Satellite Technology Ltd. Now part of Airbus.
That's awesome another old bird still going! I'm actually planning on doing a video on the evolution of the Oscar craft in the future, and that will definitely have to be mentioned in there. Cheers from California! :)
I still have a printout of telemetry I received from Oscar 11. That was back in the mid 1980s. Very exciting stuff. Used a long Yagi maybe 9 element and handheld rx. Beeb computer for satellite predictions and Beeb for decoding as well.
Somehow i think. This little satellite will tell the story of humans. When humans and all life are but dust and aliens come to find the planet that we called earth and had so many satellites orbiting around it.
My theory, while improbable, is no less unlikely than some of the other ones: Oscar was struck by a micro meteorite in just the right way for it to sever one of connections inside the battery, opening the circuit.
Could be! What's crazy about that, is that it would have to fly under the outer panel (can't hit solar cells or you'd notice on telemetry, and at the other "end", it would tear through the components), and also through that battery casing, all without warping that outer panel and disallining the turnstile antennas, so if it was, it was the most perfect hit ever!
I had my first AO7 contacts using all Heathkit equipment. The birdies were so bad that it was difficult to find the actual signal. But I had a few and it was really exciting!
I started with SAT in 1999, and had the pleasure of being able to make a large number of CW SSB QSOs via AO7, the history of this artifact is fantastic. Py3du
The HI HI Morse signal is normally vocalized as High-High, not He-He. The HI HI prosign is the Morse equivalent of LOL and pre dates the space age, so it can truly be said that AO-7 is laughing at us. 73 de G3ZVT
Good question! In short, no, because 1.in eclipse they would lose memory and have digital systems get all wonky (ao-7 was almostly analog, and it still does weird stuff now and then), and 2.by law (mainly because of reason #1) you can't build one with it. It's just not worth it to trade craft control/safety for longer operational life. Like I said though, good question and thanks for asking :)
Yup! It just dies when it has no sun, but once it gets back into the sun, it just powers right back up! No power based memory like our moden stuff, so it just never loses its startup programming.
Nicad batteries often go open circuit from overcharging/dischargeing was very common back in the remote control car days , someonr killing a battery from over charge and discharging down to zero. volts...
Maybe in RC cars, but definitely not in spacecraft. This has been the ONLY time it's happened in spacecraft. Almost all spacecraft have redundant battery control regulators that don't allow overcharging to take place. Interesting though!
That is so cool thank you so very much for that I really enjoyed this video and this is not my kind of thing I normally watch!!!! Myself personally I believe that satellites should be built with this type of flaw or detect or bypass if you will in place so that when they're done With their primary mission, they could be turned over to someone or some other agency and be repurposed simply operating off of their solar panels directly
Yes that is true. From what I looked up, it was decommissioned in 1997. In spacecraft terms, that is end of operation, regardless of functionality. AO-7 is commissioned and still allowed to be on mission, while as Prospero is not. Very interesting though!
@@retrorockets6465 In September 2011 a team at University College London's Mullard Space Science Laboratory announced plans to re-establish communications with Prospero, in time for the satellite's 40th anniversary.[3] As of September 2012, not much progress had been made in establishing contact with the satellite due to time constraints.[15] At perigee, Prospero can be seen through binoculars at magnitude +6 overhead, steady.
Why can't they use regular radio stuff to see if the beacon is still working, I take it the signal is too weak and a radio telescope is needed? And I really hope it's still going!!
Really cool stuff! I do have a question about the battery, though. You describe the battery as having 10 cells, and I have read the same in the AMSAT OSCAR-7 Technical Guide, but in the photos of the battery I count 12 cells. Can you explain my error?
Not sad at all, Oscar 7 is fascinating, and I have other projects to do, I can't focus too much. Although I will say I did read Jan's 45 page paper, so I know more than what's in the video. If I said everything I'd lose most of the viewers becaue it would be like 2 hours long haha! Can never leaned too much :)
EDIT: I understand now that it's radio equipment, I'm a ham noob sorry :) (Like the PPE gear? I'm assuming the big NOAA sat had hypergolic fuel onboard, don't know off the top of my head but that's my guess)
These are the videos I'm looking for! Keep posting please, maybe next time some Soviet stuff? But I'm not gonna complain, whatever we get is gonna be good!
Yes! Sputnik 3 and Mars 3 are very soon on the list! I'm planning to do US/USSR pattern and go back and forth, after this next christmas one of course, got something special for that :)
Agreed! It's just because it's a craft system that (usually) works the "experiments", oscar just has his radios lol. In documentation it is the Experiment Control Logic, just fancy aerospace wording :).
The background music is way too loud. And even if it wasn't so loud, it has too much midrange to work behind dialolgue. I enjoyed 8:00 - 20:50, though!
Dang I'm sorry to hear that! I've turned it down more for every video (5 now) and I still get some comments about it, on my system (300 watt monitors with sub), I can barely hear it over my voice. I still need to learn to adjust ranges instead of turning db's down, I'm really new to all of this but I'll get there! What 1910-20's era music (the music that fits the story) would you recommend that wouldn't have too much midrange? Thank you for being kind and constructive! :)
@@retrorockets6465 You're not going to talk or listen to AO-7 on a $20 Baofeng. It is an SSB satellite, not an FM satellite. AO-7 is a nice bird because it is higher than most of the other LEO sats, so it is possible to talk to Europe from the east coast of USA if the pass goes right down the middle of the Atlantic. You can't do that on the lower birds - they don't have a big enough footprint.
@@stargazer7644 I thought it used UHF and VHF frequencies? I agree with you, I'm just trying to understand it since I'm very new to radio systems (and all of this spacecraft stuff really, I just think they're cool and learning as I go).
@@retrorockets6465 They do both use UHF and VHF frequencies. SSB and CW aren't only used on HF :) But you do need a special all mode VHF/UHF radio to use them like an IC-9700. Handhelds typically only do FM. There are two types of satellite transponders - FM repeater satellites like AO-91 and SO-50 (and others) that have a single FM channel just like a ground repeater would (except the input and output channels are on different bands), and linear transponder satellites which take a range of frequencies on one band, and translate them to a range of frequencies on another band. AO-7, RS-44, XW-2B and several others work this way. Linear transponder sats can support multiple people simultaneously on different frequencies. Narrow bandwidth modes are used on these satellites such as SSB, CW, and digital. Both FM sats and linear sats use VHF and UHF frequencies. If you look at the frequency list for AO-7 mode B it says: Mode U/V (B) Linear Transponder (Inverting): Uplink: 432.1250 - 432.1750 MHz SSB/CW Downlink 145.9750 - 145.9250 MHz SSB/CW That means when you uplink at near the bottom of the band at 432.1250, your downlink comes down near the top of the band at 145.9750. Because this is an inverting transponder, if you go up with USB, you'll come down with LSB. You can pick any frequency from 432.1250 to 432.1750, though the bottom part is normally used for CW. Not all linear sats are inverting. On those sats if you go up at the bottom of the band on USB, you'll come down at the bottom too on USB. The frequency list for AO-91 says: Mode U/V FM transponder Uplink: 435.250 FM (67 Hz CTCSS) Downlink: 145.960 FM Operational - Due to battery status, please do not attempt to access while in eclipse. That means you uplink on one FM channel at 435.250 with a PL tone to activate it. You downlink at 146.960. Only one person at a time can use this satellite, just like only one person at a time can use a ground repeater. The reason a Baofeng won't work on AO-7 isn't so much due to the altitude (though that does make it harder), but because the Baofeng handheld is FM only. You need a sideband/CW rig for AO-7.
Go little satellite go, never thought I would be wishing and cheering on a a small satellite to shine. The battery issue interesting was it the Russians or Trump nah aliens definitely But I understand that just one cell stuck in the open position will do that is it recreatable ? probably, interesting rabbit hole indeed.. Thanks I had never heard of this one greetings from Australia. Interesting I subscribes and hit the bell icon for all and it defaults to none, agggg UT.......
Yeahh I know sorry about that. It was an error caused after rendering, resolutions being different in my video editor. Didn't look that way on the editing end of things and unfortunately I'd have to reupload the video to fix it. Lesson learned and thank you :)
I used cw through Oscars 6,7 and 8. Cw??? - yes! It was much easier to find my sidetone echoing back than hear my voice while talking and tuning at the same time. Mondays were qrp days. My best cw contact was using a 2 metre FM handheld, using ptt bar as a key to a simple dipole - indoors! Still have the qsl card from the guy in London. Best dx was Romania. G4BTI.
![Noob To Max With DRAGON REWORK In Blox Fruits [FULL MOVIE]](http://i.ytimg.com/vi/LnBMOinoOvA/mqdefault.jpg)
Hi, my grandmother built that satellite, along with Jan King and others. her name was Marie Marr. I have pictures and articles about the other Oscars she helped create. My grandma was a ham radio enthusiast and could build them with everyday objects and tools. She lived in Greenbelt Maryland and was commissioned by NASA to build piggy back satellites. Btw in the picture was my grandmother. Thanks for sharing your video with us.
She was amazing! When researching for the video she stood out and was in so many of the photos! I knew who she was before I knew who Jan was lol. I posted on her obituary because she was so inspiring to me. Thank you for sharing your story as well, she will always be a badass! :)
@@retrorockets6465 when I was younger, she rode a Harley Davidson. She was very progressive. The only reason she didn't go further in NASA was because she lacked a college degree. When she built Oscar 7 she was a grandmother already, so college was out.
Since the satellite is passively stabilized magnetically, the spin wasn't for extra stabilization, but for thermal control. You need the satellite to rotate constantly so sun exposure doesn't bake one side while the other freezes.
Barbecue Roll 😉
True, I'll add that as a correction as you're not wrong! Although I will point out that with the Photon prop, it's primary use is just to keep it's spin rate from decaying, can't control thermals if you stop spinnin' :)
Look at it this way, magnets are only to keep earth orientation up until the poles, but the spin rate is still needed and is all controlled by photon prop and the hysteresis bars. I will reiterate though that you are right that it handles thermal control as well, and I added a correction mentioning ya!
Spinning is a good trick.
Thank you so much for taking the time to put this video together, it is truly fascinating. I did work it and oscar 8 back in 1979 or 80 and it was considered an old bird even then. I have not looked for it in many years but perhaps I should? Again Thank You
Who else was rooting for an old satellite? It's sort of comforting to know Oscar 7 will still be up there doing its thing long after we are all dust.
It is :)
It was a thrill to communicate long-distance as far away as Europe and Venezuela through Oscar 7 using a simple hand-pointed antenna inside my apartment, along with some cobbled-together converters, radios, and stuff lying on the floor, plus a homemade orbit plotting device that showed where to point the antenna. Great fun. Many thanks to those who created Oscar 7.
That's amazing! And agreed :)
I talked through Oscar 7 this year!
Great to hear that it is still working! My first contact via OSCAR 7 (I'm in the UK) was orbit 21, a few hours after launch, with a ham in the Netherlands (using CW)..
"Aircraft grade aluminum" is marketing speak and means nothing. While far from exhaustive I have spent years at work looking over material specifications and I never once encountered the term "aircraft grade" in reference to anything by any standards organization. Also most "aircraft grade aluminum" is 6061 which is a good alloy but is as close to a generic alloy as you can get, you really should point at an airplane or satelite and say "this thing is made of lawn chair grade 6061 aluminum!"
That's like the old "computer grade" capacitors.
True! But it does sound good in a script :)
The traditional commercial marketing name for aircraft-grade aluminum (particularly 7075) is "Duralumin" or "Duraluminium."
And if you tie several weather balloons to your lawn chair like that guy did in the 90s, it's an aircraft anyway. hihi
@@kb7clx Lawn Chair Larry was in 1982.
I started satellites in the fall of 2019 and have worked A07 many times on the 10M down-link. Both CW and SSB. Always a challenge but it works. I never knew when it died or came back to life. Great video. Well done. VE4MM
That's awesome! And thank you!
I was operating OSCAR 7’s Mode U/V transponder earlier this week; occasionally the quality of the repeated SSB signals sounds slightly distorted, a condition called “FMing”. This occurs when the power drain from the transponder approaches the limits of what the solar cells can supply; it affects the frequency stability of the transponder’s oscillators, causing them to vary in frequency in time with some of the strongest SSB voice peaks. The way to avoid or at least minimize this effect is for hams to voluntarily limit the power of their uplink transmissions. 😊
Tom WA1LBK
"Fancy shrouded Thor" this is, to the date, the best description of what a Delta rocket was.
Basically just P-R to distance the Launcher from its military roots as an IRBM to better market it as highly reliable Satellite 🛰 Launcher.
"No, not that Maxim", but YES, that Maxim's son.
You're right wow!!! Thank you for mentioning that! I'll HAVE to add a note of that in the description :)
That intro was amazing. Never in my life have I felt so emotional over a hamsat...
Look up the story ISEE-3/ICE and the Reboot project - another 1970s launch that still answered a call from Earth in 2014.
Thank you for rekindling my love of spacecraft- what a comeback story!!
*PLEASE* consider doing a series on more of these derelict birds! This video was my first exposure to your channel, and 30 seconds later I subbed. To say that you've got potential on this platform would be a massive understatement.
Oh I totally agree! I think a video on the evolution of OSCAR craft is in order!
Fantastic piece of satellite history! Thank you!
Thank you as well!
The algorithm provided me with a gem of a channel.
Thank you! Let's hope it keeps providing, I know I will ;D
14 volts *max* at 14 watts? Thats 1 *AMP*. HOLY COW THATS IMPRESSIVE
What a great video. Subscribed and thumbs up. This is some history that I didn't know. Amazing that a satellite constructed so long ago could still be functional. As a ham I really enjoyed this. It kinda makes me wonder how long the lil satellite that could will make it?? This makes me wanna pull out some gear and give it a try!!
Do it! Haha hopefully you can grab him as he comes by! :) And I have a feeling he's got plenty of years left in him! Thank you as well!
Me too
I used to really enjoy working the AMSATS. I should break out my gear again one of these days.
I seriously enjoy these videos, they are so detailed and inspiring.
Thank you so much!!
I read a code book for land based wire morse telegraphers once. Theres a lot you can do with it using combinations of letters. It was like data compression but UK 1870ish style. Exactly what its date was I couldn't say but it had codes for sentances that talked of departure and arrival dates and times, ships trains coal lamp oil cargo and horses etc and never once mentioned cars or radio. One synchronized all the clocks on a railway network and thus every single clock and pocket watch in an entire town or village. I imagine someone somewhere in London had a telescope locked on Big Ben.
That's wild, telegraph goes wayy back! And yes! I remember hearing about how before that tech came along, they would use air lines and air pulses from a main clock and it was a pain to deal with haha
The telescopes were aimed at a large leather covered wooden ball in a tower at the Greenwich Observatory that was visible from the Thames docs where all the ships navigators would look to reset their chronographs at noon every day when it fell. Accurate chips chronometers were the tool that allowed for accurate East-West ocean navigation and mapping using the stars and sun to determine latitude.
Thats a crazy story....Best part being the way it was built and the people who did it. Thats a tough little satellite.
Right! I talked to Jan King quite a bit and he really laid that personal story out, the AMSAT and OSCAR teams are really something special.
Beautiful. True mad lads! Thanks for the video Ben. ❤
I restore ARC RT 328 radios, when I can. One key to lasting gadgets is shrewdness and quality of components. Keep their count low, and don't design yourself into a box. Components, like crystals, that don't last must last. Design for them to last for as long as possible. Keep things super light.
Thanks for sharing this amazing story.Great to see what a passionate team can accomplish.
I agree! Thank you for taking the time to listen to that great story :)
What an amazing story, and well told (relayed?) too! Subscribed, thanks :)
Nicee, I see what ya did there :), Thank you!!
Excellent true story . Thanks for telling us ! Great presentation !
Thank you! :)
I teared up a bit- thank you for this wonderful video
Oh trust me, I did a few times while making it! Thank you as well! :)
I remember hearing a maybe a radio ad about Oscar narrated by Lorne Greene. This was back in the day.
Magnetically stabilized.
Great video !
Thanks! :)
Great story! More! More!
Don't worry I'm on it! Already working on the next one :)
Always a fan of AO7, quite a lot of years ago, my friend John, LA2QAA (SK) and myself GM1SXX noticed a strange anomaly with AO7 while we were decoding what we liked to call'watery telemetry'... weak and warbling . Despite being in permanent sunlight, the mode switching timer was not operating accurately, which we found very strange given it was an xtal controlled timer. After exchanging some emails back and forth with Jan King W3GEY, we found out why. Due to time constraints, they couldn't source a suitable crystal for the timer to meet the launch date , so instead they concocted an RC timer to do the job. Of course such timers drift like the driven snow. It was a very interesting time in my ham journey.
That's wild! And gotta love Jan man! He helped me so much with this video
Thank you. Never knew how rediculously unlikely this QSO was!
Right! The more I researched the more rare it got.
So how come they don't just design satellites to disconnect the battery once it's shot?
Good question! Probably (just assuming) because most craft have power based memory so they'll lose programing once they lose solar power when going into eclipse. AO 7 is just that old school to where it can keep rebooting even if all power is lost. Just my guess though lol
Because you really don't want uncontrolled spacecraft doing random things whenever the sun shines on them 50 years after they were launched.
isnt that half the point of making new ones deorbit when retired?@@stargazer7644
UoSat Oscar 11 is still orbiting and transmitting telemetry too. Launched March 1984, designed and built by staff and students at the University of Surrey, under Martin Sweeting, here in the UK. Many of which went on to form Surrey Satellite Technology Ltd. Now part of Airbus.
That's awesome another old bird still going! I'm actually planning on doing a video on the evolution of the Oscar craft in the future, and that will definitely have to be mentioned in there. Cheers from California! :)
I still have a printout of telemetry I received from Oscar 11. That was back in the mid 1980s. Very exciting stuff. Used a long Yagi maybe 9 element and handheld rx. Beeb computer for satellite predictions and Beeb for decoding as well.
Somehow i think. This little satellite will tell the story of humans.
When humans and all life are but dust and aliens come to find the planet that we called earth and had so many satellites orbiting around it.
My theory, while improbable, is no less unlikely than some of the other ones: Oscar was struck by a micro meteorite in just the right way for it to sever one of connections inside the battery, opening the circuit.
Could be! What's crazy about that, is that it would have to fly under the outer panel (can't hit solar cells or you'd notice on telemetry, and at the other "end", it would tear through the components), and also through that battery casing, all without warping that outer panel and disallining the turnstile antennas, so if it was, it was the most perfect hit ever!
I had my first AO7 contacts using all Heathkit equipment. The birdies were so bad that it was difficult to find the actual signal. But I had a few and it was really exciting!
That's awesome! Communicating with/through history!
I started with SAT in 1999, and had the pleasure of being able to make a large number of CW SSB QSOs via AO7, the history of this artifact is fantastic.
Py3du
That basement was my grandmothers house in Greenbelt Maryland.
We finally have whos basement it was! Thank you! :)
@retrorockets6465 your welcome and thanks again for posting this video.
The HI HI Morse signal is normally vocalized as High-High, not He-He.
The HI HI prosign is the Morse equivalent of LOL and pre dates the space age, so it can truly be said that AO-7 is laughing at us. 73 de G3ZVT
Correct. It indicates amusement.
So would there be any advantage to building in a battery disconnect since this worked out?
Good question! In short, no, because 1.in eclipse they would lose memory and have digital systems get all wonky (ao-7 was almostly analog, and it still does weird stuff now and then), and 2.by law (mainly because of reason #1) you can't build one with it. It's just not worth it to trade craft control/safety for longer operational life. Like I said though, good question and thanks for asking :)
cant you reroute power through avswitch relay to put the battery in charge amd switch on or off with an input?
oh it is storeing energy from space amd solar... wow!!!
Yup! It just dies when it has no sun, but once it gets back into the sun, it just powers right back up! No power based memory like our moden stuff, so it just never loses its startup programming.
Nicad batteries often go open circuit from overcharging/dischargeing was very common back in the remote control car days , someonr killing a battery from over charge and discharging down to zero. volts...
Maybe in RC cars, but definitely not in spacecraft. This has been the ONLY time it's happened in spacecraft. Almost all spacecraft have redundant battery control regulators that don't allow overcharging to take place. Interesting though!
Mr. Trans does the worst Archie Leach impression ever, but those dimples are to die for.
Haha truth!
That is so cool thank you so very much for that I really enjoyed this video and this is not my kind of thing I normally watch!!!! Myself personally I believe that satellites should be built with this type of flaw or detect or bypass if you will in place so that when they're done With their primary mission, they could be turned over to someone or some other agency and be repurposed simply operating off of their solar panels directly
UK's Prospero satellite is older, and it's beacon is still running.
Yes that is true. From what I looked up, it was decommissioned in 1997. In spacecraft terms, that is end of operation, regardless of functionality. AO-7 is commissioned and still allowed to be on mission, while as Prospero is not. Very interesting though!
This would be a great piece of info to add to the video I want to do on the Black Arrow!
@@retrorockets6465 Flight spare of the Prospero satellite in the Science Museum, London.
@@retrorockets6465 In September 2011 a team at University College London's Mullard Space Science Laboratory announced plans to re-establish communications with Prospero, in time for the satellite's 40th anniversary.[3] As of September 2012, not much progress had been made in establishing contact with the satellite due to time constraints.[15] At perigee, Prospero can be seen through binoculars at magnitude +6 overhead, steady.
Why can't they use regular radio stuff to see if the beacon is still working, I take it the signal is too weak and a radio telescope is needed? And I really hope it's still going!!
Great video documentary. 😎🎙️📻
Thank you! :)
That’s incredible!!!
Really cool stuff! I do have a question about the battery, though. You describe the battery as having 10 cells, and I have read the same in the AMSAT OSCAR-7 Technical Guide, but in the photos of the battery I count 12 cells. Can you explain my error?
Very good question and I should've mentioned that. I do believe they are the 2 redundant battery charge regulators!
Is it sad that I know *more* about Oscar 7, and AMSAT in general, than the narrator of this video?
Not sad at all, Oscar 7 is fascinating, and I have other projects to do, I can't focus too much. Although I will say I did read Jan's 45 page paper, so I know more than what's in the video. If I said everything I'd lose most of the viewers becaue it would be like 2 hours long haha! Can never leaned too much :)
I noticed there's a lot of Heathkit equipment.
EDIT: I understand now that it's radio equipment, I'm a ham noob sorry :) (Like the PPE gear? I'm assuming the big NOAA sat had hypergolic fuel onboard, don't know off the top of my head but that's my guess)
Wondered if those OSCAR birds were still flying.😊
There have been over 120 OSCAR satellites since 1961. There are about 20 amateur satellites currently active.
These are the videos I'm looking for! Keep posting please, maybe next time some Soviet stuff? But I'm not gonna complain, whatever we get is gonna be good!
Yes! Sputnik 3 and Mars 3 are very soon on the list! I'm planning to do US/USSR pattern and go back and forth, after this next christmas one of course, got something special for that :)
@retrorockets6465 Hell yeah dude! Can't wait!
14:09 I think you mean 70 cm, not 70 m band!
I do! Thank you! I'll add a correction sorry, my mistake!
16:09 ECL stands for emitter connected logic. Nothing experimental for that period of time.
Agreed! It's just because it's a craft system that (usually) works the "experiments", oscar just has his radios lol. In documentation it is the Experiment Control Logic, just fancy aerospace wording :).
WWII was from 1939-1945 not the fifties (@3:28)
Yes you are correct. As I stated in the video, ham radio gained popularity in the 50's AFTER advancements in world war 2.
The background music is way too loud. And even if it wasn't so loud, it has too much midrange to work behind dialolgue. I enjoyed 8:00 - 20:50, though!
Dang I'm sorry to hear that! I've turned it down more for every video (5 now) and I still get some comments about it, on my system (300 watt monitors with sub), I can barely hear it over my voice. I still need to learn to adjust ranges instead of turning db's down, I'm really new to all of this but I'll get there! What 1910-20's era music (the music that fits the story) would you recommend that wouldn't have too much midrange? Thank you for being kind and constructive! :)
A great story
It really is!
7:05 Sure looks like a couple of Atari 800s
I think you're right! That AMSAT footage was from a later period, had to work with what little footage I could find lol
@@retrorockets6465 Great video - AO7 was fun a few years ago - had no idea it'll keep on like that, and what a crew that built it!
What does OSCAR -7 actually do?
He just a radio relay/repeater in space :). People use him to talk around the world using amateur (ham) radios.
@@retrorockets6465 You're not going to talk or listen to AO-7 on a $20 Baofeng. It is an SSB satellite, not an FM satellite.
AO-7 is a nice bird because it is higher than most of the other LEO sats, so it is possible to talk to Europe from the east coast of USA if the pass goes right down the middle of the Atlantic. You can't do that on the lower birds - they don't have a big enough footprint.
@@stargazer7644 I thought it used UHF and VHF frequencies? I agree with you, I'm just trying to understand it since I'm very new to radio systems (and all of this spacecraft stuff really, I just think they're cool and learning as I go).
@@stargazer7644 You're right that he's way to far up for a handheld, that's my bad lol, I edited my comment and thank you for your correction :)
@@retrorockets6465 They do both use UHF and VHF frequencies. SSB and CW aren't only used on HF :) But you do need a special all mode VHF/UHF radio to use them like an IC-9700. Handhelds typically only do FM.
There are two types of satellite transponders - FM repeater satellites like AO-91 and SO-50 (and others) that have a single FM channel just like a ground repeater would (except the input and output channels are on different bands), and linear transponder satellites which take a range of frequencies on one band, and translate them to a range of frequencies on another band. AO-7, RS-44, XW-2B and several others work this way.
Linear transponder sats can support multiple people simultaneously on different frequencies. Narrow bandwidth modes are used on these satellites such as SSB, CW, and digital.
Both FM sats and linear sats use VHF and UHF frequencies. If you look at the frequency list for AO-7 mode B it says:
Mode U/V (B) Linear Transponder (Inverting):
Uplink: 432.1250 - 432.1750 MHz SSB/CW
Downlink 145.9750 - 145.9250 MHz SSB/CW
That means when you uplink at near the bottom of the band at 432.1250, your downlink comes down near the top of the band at 145.9750. Because this is an inverting transponder, if you go up with USB, you'll come down with LSB. You can pick any frequency from 432.1250 to 432.1750, though the bottom part is normally used for CW. Not all linear sats are inverting. On those sats if you go up at the bottom of the band on USB, you'll come down at the bottom too on USB.
The frequency list for AO-91 says:
Mode U/V FM transponder
Uplink: 435.250 FM (67 Hz CTCSS)
Downlink: 145.960 FM
Operational - Due to battery status, please do not attempt to access while in eclipse.
That means you uplink on one FM channel at 435.250 with a PL tone to activate it. You downlink at 146.960. Only one person at a time can use this satellite, just like only one person at a time can use a ground repeater.
The reason a Baofeng won't work on AO-7 isn't so much due to the altitude (though that does make it harder), but because the Baofeng handheld is FM only. You need a sideband/CW rig for AO-7.
Go little satellite go, never thought I would be wishing and cheering on a a small satellite to shine. The battery issue interesting was it the Russians or Trump nah aliens definitely But I understand that just one cell stuck in the open position will do that is it recreatable ? probably, interesting rabbit hole indeed.. Thanks I had never heard of this one greetings from Australia. Interesting I subscribes and hit the bell icon for all and it defaults to none, agggg UT.......
Cool story bro
Great production Ben, except the credits at the end being small font, RED on BLACK.
Sorry, just about unreadable.
Yeahh I know sorry about that. It was an error caused after rendering, resolutions being different in my video editor. Didn't look that way on the editing end of things and unfortunately I'd have to reupload the video to fix it. Lesson learned and thank you :)
See also Voyager
Guy Collins Animation
Thank you! I love this guy! I remember seeing the video game one a while back :)
So the longest lasting satellite in history was dirt cheap and home built? lol, figures
Right! lol, Nasa didn't calibrate it, so it lives forever haha
o7
I used cw through Oscars 6,7 and 8. Cw??? - yes!
It was much easier to find my sidetone echoing back than hear my voice while talking and tuning at the same time. Mondays were qrp days. My best cw contact was using a 2 metre FM handheld, using ptt bar as a key to a simple dipole - indoors! Still have the qsl card from the guy in London. Best dx was Romania.
G4BTI.
That's awesome!