Interesting, I was a SDDS ( Signal Data Demodulator system ) technician at the time at a tracking station during Apollo. The equipment you are showing was unknown to me as I was downstream from the USB antenna system, about a half mile away, at the the actual tracking station where all the data was sent, decoded, and recorded and equipment called a PCM decoded all the down linked digital data. These signals had sub carriers PM and FM which contained voice and video which also had to to be decoded further by the SDDS for the digital and video data to be recorded and sent to Houston. It has been a long time, but I still remember some of the equipment and procedures. You might not be aware of it but all the timing for these systems used a Cesium beam time standard calibrated to the NBS time standard at Ft. Collins Colorado, because the spacecraft tracking with the USB required very precise timing.
@@demolitiondavedrillandblast Hello there yourself! As much as I like seeing things blown to smithereens, I also like Marcs delicate touch and information that I barely understand. You probably already gathered that I like to learn stuff.
Bugger me. That is just microwave porn you have there. Black arts indeed, every time you show the Apollo hardware, I just realise that the Apollo engineers were so utterly brilliant, it makes me want to cry. I have often said that if I could make a wish it would be that I could have been involved in some small way in the Apollo program, I wish this so much that sometimes my heart would burst.
Right. It wasn't a matter of buying off the shelf kit was it - they first had to invent it in many cases. When developing software today for instance you are building on billions of hours of work done by others. Back then you first had to design and build the computer, design all the interface standards, design all your own messaging protocols and data exchange standards, design and build the peripheral hardware, write the operating system, write the dev tools, and then you could start writing the software.
Does not make sense. If they are using the same scheme and this is the satelite equiptment, then this would transmit on downlink frequency and receive on uplink, which leads to contacting ground center, not the satelite.
Marc; i'm an avionics tech in Australia, no idea how I stumbled on these, I'm not normally a TH-cam watcher, but I have been binge watching everything over the last month and am compleaty hooked. Fascinating stuff, I'm entertained and learning something! An uncommon achievement 😝 keep up the good work.
Designed by guys in white shirts and tie, a cig hanging from left lip and a slide rule in their hands . A brilliant designed piece of equipment for its time.. and to the people who questioned why we spent the money if they just could realize all the spin off's that came off of things like this we enjoy today.
I've got to admit - I'd love to see inside those modules! I'm fascinated to see how they managed to create this masterpiece with the components they had available back then. The compact size for such a complex device makes this a masterpiece IMO.
As with every Video of you and your team, I am highly astonished on the technical details you come up with. Needles to say, that you presentation and all of your "old school" engineering skills are an inspiration !
Marc, thanks for this. I know it' may seem like magic to some, but it was solid RF engineering in the '60s. What might be even cooler would be a comparison to "modern" equipment in contemporary spacecraft. (I got my HAM license in '65 as an 11-year-old boy growing up in Southern California)
Wow! The *ABSOLUTE GENIUS* it took to design and build this system in the 1960s -- hell, it'd still be difficult to do TODAY! I can't imagine what it took to get it done in the '60s. Seriously, SERIOUSLY impressive stuff here!! The more I learn, the more I realize how much I don't know. Absolutely LOVE these videos! Keep 'em coming!!
My dad worked on department of defense radar contracts in the 60s for GE and that was one of his great electronics loves that he passed on to me. So while not directly related, a lot of these parts are familiar. This is exceptionally cool and your knowledge is impressive
I don't have a clue what the hell Marc just said but I absolutely love it. I hope he keeps doing more of these style videos. I love getting into the fundamentals of how things work. Fascinating.
I have an Electronics Degree and an Amateur Radio licence and to be honest I have to concentrate on following some of these videos. Ironically you don't need to be an expert or even knowlegable to enjoy them which I what I love about Marc's channel.
I really appreciate your putting this together. I was looking for information on how the coherent transponder mode works on Voyager, but it sounds like it's exactly the same as Apollo. Especially as you're saying they still use the same approach on ISS. Now everything is clear! Thank you so much!
Holy crap! What an incredible job, both on your part, and of course the MANY engineers who built this thing! Amazing that so much of that can be done in a chip or two today
Amazing technology of the day. Even today the same things are in use. Perhaps smaller, lower power consumption and greater transmitting power but all recognizable.
I read microwave Comms at university. I still have the text books above my desk to remind me of how little I understand of how the damned things work. My lecturer did pay me the highest complement I had at uni though: "You have one of the finest research minds of an undergraduate I have met in many years." I just wish my mental health had been in a place where I could have made a run at an EngD. Oh well. The paths left un-trodden.
Good day Marc... Since subscribing to your channel months ago one wish I have is for Voyager to come full circle back to Earth 🌍 and land in your garden for a CuriousMarc documentary.. Oh and to play that gold record with the sounds of the Earth... Romantic sigh... ♥
Hi Marc! Your videos are in a league of its own. It's way to complicated stuff for me, but I love these videos and watch from the beginning till the end. Oh and I love the sections with the elevator music by the way ;-)
ive been playing with SDR for a few years now... thought i knew a fair bit about modulation... first time ive heard of Phase Modulation with this vid!.. i know about phase but didnt realise you could modulate it to send data on..Apollo still teaching us 50 years later! :P
At 04:14 the time delay back at Houston when using "Ranging" gives distance but also the frequency shift gives velocity either away or towards the receiver using Doppler shift.
@@Richardincancale No, because the transmission frequency from the spacecraft is known. It was set & built into it before launch. It's the frequency of the transmission from the spacecraft upon reception, and the difference from the known transmission frequency, that gives you the Doppler shift from which you can calculate the the velocity of the spacecraft. Just like the Doppler shift heard from an passing fire engine or a train whistle.
@@Aengus42 What you say is true if the frequency was derived from an on-board standard like an OCXO. But if you follow Marc’s explanation the transmit frequency from the craft is tied to the received signals from earth via a PLL - the famous 221/240 translation ratio.
@@Richardincancale If that's the case then I misunderstood. Thanks, I'll go back & watch it again. But one thing puzzles me. How did Jodrell Bank in the UK track the position, velocity & landing by Doppler if their transmit frequency kept changing?
@@Aengus42 Yes I was puzzled too. The advantage of the transponder idea is accurate rangefinding by measuring round trip time (assuming you know the delay time in the transponder itself) - and receiving stations would need to be synced on the ground with the transmitter site. And the actual transmit and receive sites will change every few hours as the earth rotates…. Complicated!
Goodness me ! when you think of it in 1968/9 being able to replace a glass valve in a radio was a big thing to most people. Transistors were still a new thing.
This video is great. I worked on modern spacecraft s-band transceivers for years. The most impressive thing is just how much RF IC technology has improved since then. We were able to fit a dual receiver and single transmitter in the 2W range on a single PCB less than 100x100mm, and seeing something that is similar in performance (ours was unfortunately not fully coherent turnaround) that basically is the guide for today in its original form is super impressive.
It is nice to have a little rest after watching this video. Only fifty years before this Apollo radio was made, wireless communications used CW Morse code.
Quite right. The actual modules usually would not be repaired instead, on failure, they would just be replaced. Only us Aussies would try to fix modules because we couldn’t afford to throw them away. Ever try to find a dead component in a cordwood module with PCBs on both ends?
The wiring doesn't look as bad as the time I hooked up a 5.1 surround sound system...with two phonos, a dual tape deck, CD changer, 4K TV, LaserDisc player, Blu-Ray, reel-to-reel/8-track, ChromeCast, external antenna, XBox 360, and DCC player. It all makes sense to me. :D
thank you marc for sharing all of your fantastic discovers and you curious mind. you have a talent for speaking into videos. a calm voice and the right rythm of speaking... i'm not an english-speaking (french)person but with help of the subtitles i could learn and understand many technical words You and your team are awesome. thank you thanks and hope you make another good things. and like said the pro-fet : Ic=B.Ib :)
Me, troubleshooting an issue on my HP 8566B, thinking "How the heck did they design this in the 1970's?"... then this little piece of 1960's tech comes along. Wow. Just wow.
that's the crazy thing about this apollo hardware, these boxes all sat next to each other but the AGC, Abort Computer, these transmitters, and the Saturn V's launch computer all used different construction methods
That was deliberate. They were worried that if everything was the same and there was some unknown problem with it, it could all fail and everything would go dead at once, which would be a bad day. By making things differently maybe only one thing will go dead, and enough of the rest will still work to keep things running. That's also in part why they had different companies design and build different parts.
That is so well explained that the mighty things looks somewhat simple in the end! (I'd probably wouldn't say so if I had a glimpse at the inside of just one of these modules.... ^^ ')
Is it just me or is there no audio? Edit: nvm, had to restart TH-cam. Maybe audio hadn't processed yet. If you can't hear it, restart. Edit 2: It might also require you to like the video and subscribe before you can hear it ;)
I think TH-cam is having a problem. A few other channels have been experiencing no-audio over the past couple of days. Whether it affects your particular connection seems to be the luck of the draw. I have had no problems while other viewers have complained.
Hmm... 240/221 = (2^4*3*5)/(13*17). The numerator and denominator are relatively prime. My guess is that this overall divisor keeps the return signal away from any weird harmonics that might result from either the transmitter or the modulation itself. I'm really curious about this.
Wow, thanks for producing and sharing this kind of content. I bet this was black magic tech back when it was designed, built and used - and shrinking this RF tech down from size of a table full of equipment into these shoeboxes was even moar black magic at these days...
I'd guess that the frequency ratios are still in common use because of incremental reuse of technology and the TDRSS network. You can find the 1974 copy of the users guide and it contains some very similar looking frequencies but with multi-user capability bolted onto it. These folks were masters of backward compatibility so I wouldn't be surprised if they wanted to allow satellite platforms to simply reuse the same transmitters and receivers but upgrade to TDRSS support with changes to the equivalent of the PMP.
First of all, 1000 thanks for your great work. It is guaranteed to be written somewhere. But how much transmitter power was there on the radio transmitters from the lunar module and the transmitter power from Houston?
I know that there are recordings of the voice transmissions from the spacecraft(s), but are there data recordings/logs of all of the data received as it was received?
If they are available today: I don't know. Anyway, this has to be an gigantic (and highly boring) amount of numbers. But sure they existed. All flight controllers (although the prime customers sure have been EECOM, GNC and the trench guys) had the possibility to order printouts of those logs from 'Operations & Procedures' (an almost forgotten, but incredibly important MOCR controller) for in-mission-analysis. Not to mention that post mission evaluation strongly depended on them.
Yes, everything was recorded on instrumentation tape recorders at the receiving station itself. I'm not sure how much was recovered, but Marcel has the graph of the AGC utilization during Apollo landing (showing the overload leading to the 1202's), which most likely was made from data played back from a tape.
Okay, if you put it that way: I'm quite sure none of the anlogue tapes has survived. What quite possibly has survived is data that has already been processed by the RTCC i.e. brought into a readable and useful format. I'm quite sure I've seen trajectory data for some missions deriving from the CMCs downlinked state vector, so that's there. But systems data...ugh. Sometimes you see some bits of it in the anomaly sections of the mission reports, but a complete printout? Yikes, who'd need that today?
@@miriamn1075 I'd bet about 10% that some of the data is still around on instrumentation tapes and/or computer tapes in some vault in a NASA basement, and maybe it wasn't flooded with muddy water two or three times in hurricanes since it was stored there. Whether some of it is readable is questionable, but possible. Whether the magic decoder ring still exists to say what the data on the tape was and what it meant is a little less likely. The chances that there is complete data for even a single mission is about -100%, which is a lot less than 0%.
I still have a 10 inch reel of Scotch IRIG tape from NASA about 1964 or earlier. There were warehouses full of instrumentation tapes that were surplused and sold at auction. So the answer is: there were, but not anymore.
that´s mind blowing .look at a 60`s TV and other stuff.. how did they make this APollo stuff happen....and except on Apollo 13 no major failures Can the modules be taken out and opened are there picturs of others?
Rip it apart all right. It's the guts and how it is assembled, what parts are used that is the interesting bit. looking at the cables is a bit boring. :) I'd love to see what they used for parts. Are there any integrated circuits ? Is it all discretes ? Is some of the rf stuff dead-bug (or teflon stand-offs) or is it all on circuit boards ? i'm sitting at the tip of my chair ...
@@ydonl Not at the shariar level. He'd go into details of each component, what design challenges the original designers must've faced, an he much more. Go watch any teardown or repair video on his channel to understand what I mean.
@@anonymousarmadillo6589 I'd be careful judging levels! I have seen quite a few of Shariar's videos, both teardowns and repairs. I guess first, teardowns bore me; I just don't see much value in them. Other people seem to love them. People are different -- go figure! I think he's a good teacher, especially for people ramping up on these things, which is a good use of TH-cam. In most of the repairs I've seen, he often sorta seems to just get lucky with some fairly simple failure; I get disappointed he didn't have to work for it. It's also pretty clear that he's already been through his investigations before he turns the camera on, and that kinda takes away the fun of watching someone's genuine brainpower working through the problems in real time. And then there are the ones where he just kinda gets to do a dead-end; calls it a repair video even though he didn't repair, and mostly just talked a lot about things that don't have much to do with finding and/or fixing the problem... that disappoints me! I haven't yet seen one of this repairs that really impressed me; all the ones I've seen were either too simple, or just plain unsuccessful. I also often get this impression that we went from "broken" to "working" without really knowing what was wrong and how it was fixed. It must have been in there somewhere... maybe I missed it! So many words. Actually, one of the things that scares me is that his bench his too clean, and the only things we ever see on it are nice new test instruments, and tools, and cats. I wanna see a gloriously disassembled device of one kind of another, old and crusty and truly broken, even hopeless, being brought back to life through sheer determination. That brainpower thing is what interests me, and it's what Marc does consistently. Live, in real time, working through the problems by applying all kinds of interesting techniques. He doesn't spend time on "conventional" teardowns and background information I suspect partly because he assumes you already know all that stuff, and partly because he wants to save time in the video. I've never seen any repair series anywhere that comes close to the Apollo guidance series with Marc and his team. Truly impressive stuff, and I consider it unmatched. The recent series on the HP 9825 also contained a lot of impressive brainpower working in real time to figure out one problem after another, not just identifying a bad component and replacing it and getting back on the road the way we hope most of our own repairs go! HIs persistence is phenomenol. It teaches me something to see him working through obstacle after obstacle, and finally get to the end and fix the thing. Always focused on that goal. I also really like FeedbackLoop for the same reasons; he doesn't spend a lot of time explaining a long series of little things, but sticks to working through the diagnosis and repair, sometimes quite difficult ones. Another one that really uses his brain and makes miracles happen is My Messy Lab. Even though his English makes it a little hard for me to follow at times, his repair skills are quite impressive, and he has projects where at the beginning, I'm saying "I don't believe you can fix that!" because it's such a mess, but then at the end I'm saying "I can't believe you fixed that!" because it's in such great shape.
Will you open the individual modules after having it made running again? It seems to be many years ahead of its time - It would be so good to see how they made it!
I'm certain that if modern 21st century components were used for computers and GNC stuff onboard Apollo vehicles they would be tiny fraction of the size and weight of the actual equipment used in the 1960s. But analogue electronics is a mystery to me. How much smaller and lighter would this RF stuff be with today's technology?
It would be interesting to see in tabular form what electronic hardware failed on each Apollo flight. I'm sure it's buried in the long mission reports.
are you sure any failed at all ? IT couldn`t bee too much because alle missions were successfull except Nr 13... what I know is that no AGC every failed on a mission
i wish we had a change to see it working :P may be trying to stream a youtube video using it :P and whats the limits ie distance and bitrate limits :P but probably that's not possible because of used out of allowed power and frequency limits :P
Maybe, but it is only 10 watts. Microwave ovens are 1000 watts. Frequency is indeed the same. In real situation, all this energy is projected earthwards, of course.
That does not look too terribly much different than the Motorola UHF/VHF repeaters of a similar age same basic modular design. I have one sitting around somewhere.
It must have been extremely challenging to achieve any of these functions with 60's components. Even dividing by 2 at modest frequency would have been tough. Despite all their electronic magic they didn't master straight nomenclature marking on the boxes. Did the drawing say "mark nomenclature as poorly as possible as shown".
I'm fine in the digital realm... but, to me analogue is black magic and RF is even more black magic and microwave is even more black magic still.... I feel like I'm being initiated into a cargo cult. ;)
Please please please don't ever stop making these videos, they are just absolutely amazing and ground breaking!
Not only ground breaking, also out of this world! :)
Interesting, I was a SDDS ( Signal Data Demodulator system ) technician at the time at a tracking station during Apollo. The equipment you are showing was unknown to me as I was downstream from the USB antenna system, about a half mile away, at the the actual tracking station where all the data was sent, decoded, and recorded and equipment called a PCM decoded all the down linked digital data. These signals had sub carriers PM and FM which contained voice and video which also had to to be decoded further by the SDDS for the digital and video data to be recorded and sent to Houston. It has been a long time, but I still remember some of the equipment and procedures. You might not be aware of it but all the timing for these systems used a Cesium beam time standard calibrated to the NBS time standard at Ft. Collins Colorado, because the spacecraft tracking with the USB required very precise timing.
I believe that Marc has a Cesium beam time standard. I could be misremembering.
@@TechGorilla1987 Fancy seeing you here TG.
@@demolitiondavedrillandblast Hello there yourself! As much as I like seeing things blown to smithereens, I also like Marcs delicate touch and information that I barely understand. You probably already gathered that I like to learn stuff.
Bugger me. That is just microwave porn you have there. Black arts indeed, every time you show the Apollo hardware, I just realise that the Apollo engineers were so utterly brilliant, it makes me want to cry. I have often said that if I could make a wish it would be that I could have been involved in some small way in the Apollo program, I wish this so much that sometimes my heart would burst.
Right. It wasn't a matter of buying off the shelf kit was it - they first had to invent it in many cases. When developing software today for instance you are building on billions of hours of work done by others. Back then you first had to design and build the computer, design all the interface standards, design all your own messaging protocols and data exchange standards, design and build the peripheral hardware, write the operating system, write the dev tools, and then you could start writing the software.
@@richardclarke376 And it all had to survive 9gs, two different atmospheric pressures, and potentially blobs of floating peanut butter.
Marc: Err hi, is this International Space Station?
ISS: Yes, but how did you get on this frequency?
Marc: Well you wouldn't believe this...
*Everyone else using internet to talk with the ISS*: '-'
Does not make sense. If they are using the same scheme and this is the satelite equiptment, then this would transmit on downlink frequency and receive on uplink, which leads to contacting ground center, not the satelite.
Yea, and they are probably incompatible
@@neves5083 no, many HAM's can make direct calls on the 2m band(144-145mhz)
@@NikiBretschneider Oh, did not expect you here :D
Nothing like a bit of solid 60’s RF engineering to put a smile on ones face 👍😀
Marc; i'm an avionics tech in Australia, no idea how I stumbled on these, I'm not normally a TH-cam watcher, but I have been binge watching everything over the last month and am compleaty hooked. Fascinating stuff, I'm entertained and learning something! An uncommon achievement 😝 keep up the good work.
Thank you Marc for all this S-band magic spaghetti content.
Designed by guys in white shirts and tie, a cig hanging from left lip and a slide rule in their hands . A brilliant designed piece of equipment for its time.. and to the people who questioned why we spent the money if they just could realize all the spin off's that came off of things like this we enjoy today.
I've got to admit - I'd love to see inside those modules! I'm fascinated to see how they managed to create this masterpiece with the components they had available back then. The compact size for such a complex device makes this a masterpiece IMO.
As with every Video of you and your team, I am highly astonished on the technical details you come up with. Needles to say, that you presentation and all of your "old school" engineering skills are an inspiration !
Marc, thanks for this. I know it' may seem like magic to some, but it was solid RF engineering in the '60s. What might be even cooler would be a comparison to "modern" equipment in contemporary spacecraft. (I got my HAM license in '65 as an 11-year-old boy growing up in Southern California)
in a russion spce craft it looks exactly like this :=)
@@bobl78 if it works, it works!
You can fit everything but the power amp into a USB SDR dongle or two if you want to support the ranging functions
Wow! The *ABSOLUTE GENIUS* it took to design and build this system in the 1960s -- hell, it'd still be difficult to do TODAY! I can't imagine what it took to get it done in the '60s. Seriously, SERIOUSLY impressive stuff here!!
The more I learn, the more I realize how much I don't know. Absolutely LOVE these videos! Keep 'em coming!!
...and done before the decade was out!
I love the enthusiasm you have for these kind of things.. I can never find this from anyone else in reality. Thankyou for your video's!
Wow. Brought back all those memories of learning RF in school. Now I remember why I didn't choose that path....
My dad worked on department of defense radar contracts in the 60s for GE and that was one of his great electronics loves that he passed on to me. So while not directly related, a lot of these parts are familiar. This is exceptionally cool and your knowledge is impressive
I don't have a clue what the hell Marc just said but I absolutely love it. I hope he keeps doing more of these style videos. I love getting into the fundamentals of how things work. Fascinating.
So nice to watch this vintage Apollo stuff! It's
amazing to see that space-technology from years back.
Who the hell give such a video a thumbs down???
Please never stop making videos Marc!
The people who gave it thumbs down were probably hoping he'd get it working in this episode! Patience, guys…
I have an Electronics Degree and an Amateur Radio licence and to be honest I have to concentrate on following some of these videos. Ironically you don't need to be an expert or even knowlegable to enjoy them which I what I love about Marc's channel.
I really appreciate your putting this together. I was looking for information on how the coherent transponder mode works on Voyager, but it sounds like it's exactly the same as Apollo. Especially as you're saying they still use the same approach on ISS. Now everything is clear! Thank you so much!
would have loved taking a look at such a project in uni, finally doing something with all of that knowledge.
Another video to add to my Curious Marc marathon tonight when I get some time to watch these! You get to play with the coolest stuff I tell you
Holy crap! What an incredible job, both on your part, and of course the MANY engineers who built this thing! Amazing that so much of that can be done in a chip or two today
Superb work Mark! Amazing to see your videos!
Amazing technology of the day. Even today the same things are in use. Perhaps smaller, lower power consumption and greater transmitting power but all recognizable.
I'm happy to see Mike is becoming a regular
I read microwave Comms at university. I still have the text books above my desk to remind me of how little I understand of how the damned things work.
My lecturer did pay me the highest complement I had at uni though: "You have one of the finest research minds of an undergraduate I have met in many years." I just wish my mental health had been in a place where I could have made a run at an EngD. Oh well. The paths left un-trodden.
This is pure gold !! 🤩🤩🤩
Can't wait for the next episode! This is so exiting!
Good day Marc... Since subscribing to your channel months ago one wish I have is for Voyager to come full circle back to Earth 🌍 and land in your garden for a CuriousMarc documentary.. Oh and to play that gold record with the sounds of the Earth... Romantic sigh... ♥
It’s insane that you get to do this stuff.
Hi Marc! Your videos are in a league of its own. It's way to complicated stuff for me, but I love these videos and watch from the beginning till the end. Oh and I love the sections with the elevator music by the way ;-)
ive been playing with SDR for a few years now... thought i knew a fair bit about modulation... first time ive heard of Phase Modulation with this vid!.. i know about phase but didnt realise you could modulate it to send data on..Apollo still teaching us 50 years later! :P
At 04:14 the time delay back at Houston when using "Ranging" gives distance but also the frequency shift gives velocity either away or towards the receiver using Doppler shift.
I guess the speed derived from Doppler shift needs to be divided by two, to allow for the outbound and return legs both being shifted.
@@Richardincancale No, because the transmission frequency from the spacecraft is known. It was set & built into it before launch.
It's the frequency of the transmission from the spacecraft upon reception, and the difference from the known transmission frequency, that gives you the Doppler shift from which you can calculate the the velocity of the spacecraft.
Just like the Doppler shift heard from an passing fire engine or a train whistle.
@@Aengus42 What you say is true if the frequency was derived from an on-board standard like an OCXO. But if you follow Marc’s explanation the transmit frequency from the craft is tied to the received signals from earth via a PLL - the famous 221/240 translation ratio.
@@Richardincancale If that's the case then I misunderstood. Thanks, I'll go back & watch it again.
But one thing puzzles me. How did Jodrell Bank in the UK track the position, velocity & landing by Doppler if their transmit frequency kept changing?
@@Aengus42 Yes I was puzzled too. The advantage of the transponder idea is accurate rangefinding by measuring round trip time (assuming you know the delay time in the transponder itself) - and receiving stations would need to be synced on the ground with the transmitter site. And the actual transmit and receive sites will change every few hours as the earth rotates…. Complicated!
Fantastic, i love rf circuits. Greetings from Brazil.
Goodness me ! when you think of it in 1968/9 being able to replace a glass valve in a radio was a big thing to most people. Transistors were still a new thing.
This video is great. I worked on modern spacecraft s-band transceivers for years. The most impressive thing is just how much RF IC technology has improved since then. We were able to fit a dual receiver and single transmitter in the 2W range on a single PCB less than 100x100mm, and seeing something that is similar in performance (ours was unfortunately not fully coherent turnaround) that basically is the guide for today in its original form is super impressive.
"we could be silly and open it"
spit my coffee !
It is nice to have a little rest after watching this video. Only fifty years before this Apollo radio was made, wireless communications used CW Morse code.
21st century archaeology --the amazing technology of earlier civilizations. What a time to be alive!
I followed it all. Thanks. Brilliant. This is amazing.
Thanks for the video...this is great!
Quite right. The actual modules usually would not be repaired instead, on failure, they would just be replaced. Only us Aussies would try to fix modules because we couldn’t afford to throw them away. Ever try to find a dead component in a cordwood module with PCBs on both ends?
Don't watch those Pakistan videos of guys rewinding car starters and rebuilding car batteries!!!!
was just telling my wife over dinner how i discovered the highest level of nerds ive seen so far! XD Wicked!!
A handbook of how it was designed should be made to give the full design as a presentation in the final year of engineering
The wiring doesn't look as bad as the time I hooked up a 5.1 surround sound system...with two phonos, a dual tape deck, CD changer, 4K TV, LaserDisc player, Blu-Ray, reel-to-reel/8-track, ChromeCast, external antenna, XBox 360, and DCC player. It all makes sense to me. :D
That stuff is magic! Thanks for this episode!
Blew my mind like usual!
Thank you for sharing in a missing video full support here👍👍👍
Fascinating! 🖖
Always good when it does what it must
thank you marc for sharing all of your fantastic discovers and you curious mind.
you have a talent for speaking into videos. a calm voice and the right rythm of speaking...
i'm not an english-speaking (french)person but with help of the subtitles i could learn and understand many technical words
You and your team are awesome. thank you
thanks and hope you make another good things.
and like said the pro-fet : Ic=B.Ib
:)
Me, troubleshooting an issue on my HP 8566B, thinking "How the heck did they design this in the 1970's?"... then this little piece of 1960's tech comes along. Wow. Just wow.
that's the crazy thing about this apollo hardware, these boxes all sat next to each other but the AGC, Abort Computer, these transmitters, and the Saturn V's launch computer all used different construction methods
That was deliberate. They were worried that if everything was the same and there was some unknown problem with it, it could all fail and everything would go dead at once, which would be a bad day. By making things differently maybe only one thing will go dead, and enough of the rest will still work to keep things running. That's also in part why they had different companies design and build different parts.
That is so well explained that the mighty things looks somewhat simple in the end!
(I'd probably wouldn't say so if I had a glimpse at the inside of just one of these modules.... ^^ ')
Thank you Marc
Pretty slick for 1969
Thanks, Marc!
Great video!!👏👏
Is it just me or is there no audio?
Edit: nvm, had to restart TH-cam. Maybe audio hadn't processed yet. If you can't hear it, restart.
Edit 2: It might also require you to like the video and subscribe before you can hear it ;)
Not just you.
Audio is fine
There is no audio for me at all.
TH-cam temporary fart? I have audio.
I think TH-cam is having a problem. A few other channels have been experiencing no-audio over the past couple of days. Whether it affects your particular connection seems to be the luck of the draw. I have had no problems while other viewers have complained.
Speechless... #thanks
"Roger Houston, switching to encrypted medical channel." Whenever "Santa Claus" was in close proximity!
_"So now you know how it works."_
I do? I mean, YES! I do!
Next Year's Project: "So we just found this Apollo Service Module to work with our transmitter box!"
Good stuff!
Hmm... 240/221 = (2^4*3*5)/(13*17). The numerator and denominator are relatively prime. My guess is that this overall divisor keeps the return signal away from any weird harmonics that might result from either the transmitter or the modulation itself. I'm really curious about this.
I love you guys.
What were the specific phase and frequency modulation types used? Basic 2 position FSK and 4 position PSK or something more data dense?
Wow, thanks for producing and sharing this kind of content. I bet this was black magic tech back when it was designed, built and used - and shrinking this RF tech down from size of a table full of equipment into these shoeboxes was even moar black magic at these days...
Once the receiver PLL achieves a lock, perhaps the error signal sent to the VCO could be used as an indicator of spacecraft velocity?
If you ever wanted to put a TWT amplifier in your lab some old Varian C-band amps can be had quite affordably on eBay from time-to-time.
What about all the telemetry streams from all the different systems?
Audio is broken. TH-cam released the video without finishing encoding properly...
It took time for TH-cam to receive the microwave signal...
@@IBM_Museum Their PLL unlocked.
I'd guess that the frequency ratios are still in common use because of incremental reuse of technology and the TDRSS network. You can find the 1974 copy of the users guide and it contains some very similar looking frequencies but with multi-user capability bolted onto it. These folks were masters of backward compatibility so I wouldn't be surprised if they wanted to allow satellite platforms to simply reuse the same transmitters and receivers but upgrade to TDRSS support with changes to the equivalent of the PMP.
Now it is working
First of all, 1000 thanks for your great work.
It is guaranteed to be written somewhere. But how much transmitter power was there on the radio transmitters from the lunar module and the transmitter power from Houston?
About 10W from the lunar module, and 20 kW from the largest ground transmitters. See the episode about the power amp.
@@CuriousMarc THX ❤❤
I know that there are recordings of the voice transmissions from the spacecraft(s), but are there data recordings/logs of all of the data received as it was received?
If they are available today: I don't know. Anyway, this has to be an gigantic (and highly boring) amount of numbers.
But sure they existed. All flight controllers (although the prime customers sure have been EECOM, GNC and the trench guys) had the possibility to order printouts of those logs from 'Operations & Procedures' (an almost forgotten, but incredibly important MOCR controller) for in-mission-analysis. Not to mention that post mission evaluation strongly depended on them.
Yes, everything was recorded on instrumentation tape recorders at the receiving station itself. I'm not sure how much was recovered, but Marcel has the graph of the AGC utilization during Apollo landing (showing the overload leading to the 1202's), which most likely was made from data played back from a tape.
Okay, if you put it that way: I'm quite sure none of the anlogue tapes has survived. What quite possibly has survived is data that has already been processed by the RTCC i.e. brought into a readable and useful format. I'm quite sure I've seen trajectory data for some missions deriving from the CMCs downlinked state vector, so that's there. But systems data...ugh. Sometimes you see some bits of it in the anomaly sections of the mission reports, but a complete printout? Yikes, who'd need that today?
@@miriamn1075 I'd bet about 10% that some of the data is still around on instrumentation tapes and/or computer tapes in some vault in a NASA basement, and maybe it wasn't flooded with muddy water two or three times in hurricanes since it was stored there. Whether some of it is readable is questionable, but possible. Whether the magic decoder ring still exists to say what the data on the tape was and what it meant is a little less likely. The chances that there is complete data for even a single mission is about -100%, which is a lot less than 0%.
I still have a 10 inch reel of Scotch IRIG tape from NASA about 1964 or earlier. There were warehouses full of instrumentation tapes that were surplused and sold at auction. So the answer is: there were, but not anymore.
that´s mind blowing .look at a 60`s TV and other stuff.. how did they make this APollo stuff happen....and except on Apollo 13 no major failures
Can the modules be taken out and opened are there picturs of others?
Rip it apart all right. It's the guts and how it is assembled, what parts are used that is the interesting bit. looking at the cables is a bit boring. :) I'd love to see what they used for parts. Are there any integrated circuits ? Is it all discretes ? Is some of the rf stuff dead-bug (or teflon stand-offs) or is it all on circuit boards ? i'm sitting at the tip of my chair ...
You should invite shariar from the Signal Path to do a detailed walkthrough!
Didn't Marc just do a pretty detailed walkthrough?
@@ydonl Not at the shariar level. He'd go into details of each component, what design challenges the original designers must've faced, an he much more. Go watch any teardown or repair video on his channel to understand what I mean.
@@anonymousarmadillo6589 I'd be careful judging levels! I have seen quite a few of Shariar's videos, both teardowns and repairs. I guess first, teardowns bore me; I just don't see much value in them. Other people seem to love them. People are different -- go figure! I think he's a good teacher, especially for people ramping up on these things, which is a good use of TH-cam. In most of the repairs I've seen, he often sorta seems to just get lucky with some fairly simple failure; I get disappointed he didn't have to work for it. It's also pretty clear that he's already been through his investigations before he turns the camera on, and that kinda takes away the fun of watching someone's genuine brainpower working through the problems in real time. And then there are the ones where he just kinda gets to do a dead-end; calls it a repair video even though he didn't repair, and mostly just talked a lot about things that don't have much to do with finding and/or fixing the problem... that disappoints me! I haven't yet seen one of this repairs that really impressed me; all the ones I've seen were either too simple, or just plain unsuccessful. I also often get this impression that we went from "broken" to "working" without really knowing what was wrong and how it was fixed. It must have been in there somewhere... maybe I missed it! So many words.
Actually, one of the things that scares me is that his bench his too clean, and the only things we ever see on it are nice new test instruments, and tools, and cats. I wanna see a gloriously disassembled device of one kind of another, old and crusty and truly broken, even hopeless, being brought back to life through sheer determination.
That brainpower thing is what interests me, and it's what Marc does consistently. Live, in real time, working through the problems by applying all kinds of interesting techniques. He doesn't spend time on "conventional" teardowns and background information I suspect partly because he assumes you already know all that stuff, and partly because he wants to save time in the video. I've never seen any repair series anywhere that comes close to the Apollo guidance series with Marc and his team. Truly impressive stuff, and I consider it unmatched. The recent series on the HP 9825 also contained a lot of impressive brainpower working in real time to figure out one problem after another, not just identifying a bad component and replacing it and getting back on the road the way we hope most of our own repairs go! HIs persistence is phenomenol. It teaches me something to see him working through obstacle after obstacle, and finally get to the end and fix the thing. Always focused on that goal.
I also really like FeedbackLoop for the same reasons; he doesn't spend a lot of time explaining a long series of little things, but sticks to working through the diagnosis and repair, sometimes quite difficult ones.
Another one that really uses his brain and makes miracles happen is My Messy Lab. Even though his English makes it a little hard for me to follow at times, his repair skills are quite impressive, and he has projects where at the beginning, I'm saying "I don't believe you can fix that!" because it's such a mess, but then at the end I'm saying "I can't believe you fixed that!" because it's in such great shape.
Will you open the individual modules after having it made running again?
It seems to be many years ahead of its time - It would be so good to see how they made it!
No, they are soldered in and not easily removable. Unless we have to because a module is broken of course.
I'm certain that if modern 21st century components were used for computers and GNC stuff onboard Apollo vehicles they would be tiny fraction of the size and weight of the actual equipment used in the 1960s. But analogue electronics is a mystery to me. How much smaller and lighter would this RF stuff be with today's technology?
Soooooo coooool
What's the end game here? Are you going to try and power the unit up? It's all fascinating, regardless!
How can I go to sleep if I haven't watched Marc's latest Apollo comms video? I would not sleep very well.
Wondering how small the modern equivalent is.
It would be interesting to see in tabular form what electronic hardware failed on each Apollo flight. I'm sure it's buried in the long mission reports.
are you sure any failed at all ? IT couldn`t bee too much because alle missions were successfull except Nr 13... what I know is that no AGC every failed on a mission
i wish we had a change to see it working :P may be trying to stream a youtube video using it :P and whats the limits ie distance and bitrate limits :P
but probably that's not possible because of used out of allowed power and frequency limits :P
Is it hazardous to be around while its functioning ?
Maybe, but it is only 10 watts. Microwave ovens are 1000 watts. Frequency is indeed the same. In real situation, all this energy is projected earthwards, of course.
That does not look too terribly much different than the Motorola UHF/VHF repeaters of a similar age same basic modular design. I have one sitting around somewhere.
🤯
"it looks complicated because it is"
Nerding at its best
It must have been extremely challenging to achieve any of these functions with 60's components. Even dividing by 2 at modest frequency would have been tough. Despite all their electronic magic they didn't master straight nomenclature marking on the boxes. Did the drawing say "mark nomenclature as poorly as possible as shown".
Not challenging at all when NASA had a huge budget and could spare no expense in buying the latest technology at the time.
... хоспаде, до сих пор ведут маркетинговую компанию, как будто они там были (((
I'm fine in the digital realm... but, to me analogue is black magic and RF is even more black magic and microwave is even more black magic still.... I feel like I'm being initiated into a cargo cult. ;)
Pretty soon you will be able to buy a Chinese clone for only $4.99 with free shipping !
Русские есть ? Рассказывайте что поняли
Speak for yourself Marc please? Even knowing it's got 5 radios it STILL looks bloody complicated to me! :)
No video and Audio 😂