The Computer that Controlled the Saturn V (Behind the Scenes ft Linus Tech Tips) - Smarter Every Day

ESMA Destin this is smarter every day to the second channel where I like to take more in-depth looks on different things technically in this case this is a memory module for the Saturn 5 lb DC launch vehicle digital computer now I like to to learn about Rockets it's kind of my thing and Linus from Linus tech tips he's a computer guy right so we are really interested in this stuff from different perspectives but we're talking to a very interesting person Luc Tali he worked at IBM here in Huntsville during the 60s during Apollo also during the 70's and and he knows this thing inside and out so this is a really fascinating thing because we kind of know what we're talking about in our respective areas but it feels like Luke knows all of the things and he's just running circles around us so this is fascinating I hope you enjoy this and let's take a deeper look at the lvdc memory module and just how all this stuff works while you're watching this please consider subscribing to this the second channel if at some point along the way you learn something that you think brought value to your life if not no big deal but if you do please consider hitting that bell to turn on notifications for the second channel anyway let's go get smarter on the saturn v launch vehicle digital computer look at this device right here don't touch this with your fingers yeah but look I knew this looks but you see how it looks very similar to what we're doing right now similar yeah we're taking a hard drive and we're plugging it in and this plugs in right see that yeah here I'm gonna I'm gonna pick one up as a prop so this is a logic controller excuse me a logic card this is a logic card for the computer that flew the Saturn 5 rocket really yeah and we're about to go meet the guy at IBM that worked on this oh no it's it's a special magnesium lithium alloy so it'll corrupt so you can't ever mind you touch it like that yep okay that looked like a safe and that was just to save weight then yes exactly yeah exactly like literally every gram or excuse me every ounce whatever yeah it doesn't matter yeah so in that crazy and so each one of these these are like this like some of the first transistor technology that was miniaturized this is a big deal man okay so what we're gonna do is I'm gonna go to the US Space and Rocket Center and I'm gonna show you this computer cool that flew the Saturn 5 rocket cuz this is like your whole Jam right this is my jam you know I guess it yeah okay let's do it is this interesting at all of you oh yeah no this is incredible so you have some guys there that can like walk us through kind of the speeds and feeds and like how it all worked and all that yes cool he will say this is not like an 8-bit system it's weird got it yeah it's very very weird so you see the you see this ring over here yeah so that's that's the computer that's the computer well the computer sits on that and shot it and there was a reason to mount it as a ring as opposed to just you know some other configuration because you want to balance a rocket right you want the center of gravity be right in the center of the rocket so this is what I wanted to show you so this is the brain for the Saturn 5 rocket if you look up right here this is the instrumentation ring and so they had computers on here that were digital this right here is the launch vehicle digital computer that is it that's like the original so this is this so there's still that module we were holding before yes there's only like eight of them yeah at least in this chunk of it this right here is a memory module okay and if you look really really really close really close you see those little bitty rings yeah okay look right here look at that do you see that holy smokes so they're just it looks like zip ties on chicken wire okay those are bits those are physical bits so you see that screen yeah these are wires that go down to these boards right here right yeah on each node you have an iron ring and depending on how the iron ring is magnetized that's a one or a zero that's how they programmed at this computer seriously so look at this right here so by hand by hand yes I threaded these wires through that I mean who has a study in Italy I don't even think you could build one of these today if you wanted to that's incredible so you get about a hundred kilobytes or kilobits Wow so like what like 15 right here for you something like the whole thing the whole module eight of those modules and the whole computer adds up to a hundred twelve hundred twelve kilobytes but the magic of all this is that it was done by hand and shoved on that ring right there and then sent to the moon and a lot all the way to the moon I guess but yeah you got it exactly this gotcha orbit and then there was another thing that happened on the Apollo spacecraft itself I got you and they're cool that's unreal so these are the memory modules and on the other side of this you can actually see the computer logic cards themselves you wanna see that oh yeah for sure yeah let me show you that so follow pillar yes okay so you remember I told you not to touch the stuff right yeah okay so this is what happens if you touch it yeah so it's a I think it's magnesium lithium alloy for weight just like you said and this just happens like it deteriorates no matter what right it's a losing battle to try to fight it but each one of these logic cards had those look you can see just down in there yeah sim and so it's like it's not expandable memory these are actually cards that you put in to do the processing Wow so anyway this was cutting edge technology back in the day like this was a quantum leap in computing power at the time and it also had to be rugged enough to fly yeah anyway I just want to show you that oh that's that's incredible okay and we have a guy here that can actually walk us through it talk to us about it sounds good it's that cool I'm Luke Talley and at this time in 1969 I was a senior associate engineer at IBM in Huntsville that's awesome and you were over there working on the instrument unit all the flight evaluations team that we evaluated the data that came back and looked for everything that might go wrong or did go wrong or did go right and to be clear this is for the Saturn 5 not for the Apollo spacecraft that's correct so this is for the Saturn 5 is to reuse so your computer pointed the rocket that's right awesome we steered the rocket which which ones you that's me that's you yeah when was this like 1969 I think you look better now man yeah this was the aluminized captain sheets that we used to cover the equipment and the cables because we after we started looking at it we found that several of the cables that were going into the several of the boxes had failed as well and then we did a Sun angle calculation based on the output from the platform system yeah and calculated where the Sun should be and then we went in and looked at temperature measurements in those areas and sure enough they were just climbing my Ganga it'll liquefied of that that after that the rest of the Fleischmann after you put this on and just solve the problem yeah so gimble drift was a big deal oh yeah drift gyro drift was always a problem that kills you if anything yes because that this computer system senses that as true motion it doesn't know any different gyro says I'm moving I must be moving but you said that the computer has a two-second loop it's comparing where it's at versa it's reading that it's reading that platform 25 times a second every 40 milliseconds it's taking a reading of where it is and where it's headed so but how do you account for gyro jeff'd if you can't like point at a star and recalibrate you your u s-- u zero it at launch and then you know how much it's gonna drift and you trust it you just trust it yep holy cow that's what you gotta do you got to build a system that doesn't have that much drift if you have a long-duration mission then you have to worry about start tracking in this kind of stuff because when you integrate you integrate you at the plus C and right now you start yeah the plus C it to him the plus C's the killer yeah [Laughter] been there float that test me I'm glad you didn't plug it when it counted right I had a retired Navy admiral teaching thermodynamics this guy had memorized the steam tables to five places at least it was good I mean you know what's the enthalpy and entropy and all that kind of stuff you know and he'd rattle off the numbering my god he's got to be looking stronger gun I didn't do amazing he just knew it oh yeah so he'd been missing submarines longer than ten time long and I've been around at that time I guess thermodynamics check this out yeah that's a that's a pristine logic card yeah where'd you get this thing oh I got it from a guy in town he's a collector can you tell me what that is because I don't really understand it to be honest with you so so to be clear here this is Luke Talley he worked on the Apollo now excuse me the saturn v launch control computer is that correct okay all right this plugs into that bow okay on the lvdc the launch vehicles well it could be the one okay it goes right there okay what does it do well these are the logic modules for the computer on the lvdc on the Saturn so there are let's see this one now has one two three four five one two three four five twenty five so this is if this is out of one of these which it appears to be this is probably out of an LED a-ok the ovc has 35 modules on a on a board okay we call these MIBs Multi inner layer connector boards or whatever it was called yeah minor detail I guess so we had 35 of these there was 35 on this side then there's 35 on the other side the wings sticking out of each of these is a these things poking out the side or your heat sinks so you plug it into the rack but we're actually pumping coolant through this rack to cool these things this thing dissipated the lvdc dissipate around 100 watts the OBD a was probably closer to 200 190 watts something like that this one was probably 85 or 90 somewhere in that range so this was all what's called T squared L each one of these modules now only contain we didn't have any integrated circuits so the spacecraft now they did have some small scale integrated circuits built by Raytheon for them for that computer this one we did not all right so we have discrete transistors inside each of these modules I just happen to have one okay hold that you can see up here there's two little squares Wow this each of those is one transistor these two little shiny pieces up here in the corner each of those is one transistor they're about 25 thousandths of an inch square 1/32 of an inch roughly all right so each one of these modules would have anywhere from two to eight of these transistors this one has more something that might be an inverter draws more current but have only a few this would be in a flip-flop a logic gate and it would have multiple you know probably up to eight and it's not a thermal issue how many is okay the back of it this thing here these little black blobs or resistors so if you look at the front you see the two transistors and them look like the wires that lead down the conductor pattern and on the back you see the resistors there's also some conductor patterns so they start out with this aluminum oxide aluminum they call it straight they print these patterns like you're printing a t-shirt all right then you put it in an oven and fire it yeah when you fire the thing then that hardens that you bring it out each of these transistors if you can look real close they're three tiny little balls of solder on the bottom of each one take it where the conductor pattern comes together you stand it up on the three solder balls put it back in another oven heat it again and those the melting of those little solder balls will align that transistor perfect the surface tension of that melting will align that transistor perfectly with that conductor pattern they tried all kind of neat ways to do it that turned out to be about as neatest there is today you hear about ball grid array attachments that's the same technology the resistors on the back they would have to take an ultrasonic scribe and scrape those until they got to the exact number they needed to range because that's not that's not enough space to use your traditional little cylindrical resistor no no of course not you're basically 1,300 ohms is 1,800 we don't care it round or flat so you're basically taking the kind of the area in between these and you're you're scratching away enough of the conductive material that you just create the resistance you need if you look very close you can see where they've been scratched yeah it looks like it kind of looks like I like a cheese like the Swiss cheese or something to call that trimmed so basically you hook it up to a Wheatstone bridge the scribe comes down start scraping until it gets down to supposed to be twelve hundred ohms we gets to be twelve hundred lifts off it stops it blows the stuff off of and then they coat it with some red goop to keep it from my guests eye corroding or yeah yeah I would think this more than likely is out of the numbers and all look like the six thousand numbers look like Saturn numbers but most of the logic in here had pretty much almost a full board really so I brought you something thinking I would impress you and you're like take it away boy yeah it's pretty good one yeah so we have something else I'd like to have a few little widget so - she was showing this you go you go ahead I think you're more familiar with how it works than me well I'm just gonna hand it to you the memory module you have to go to the Antiques Roadshow that room realize that this is core memory so you have these magnetic cores you have the wires feeding through the cores you push a current down through a wire right if you got a wire you if currents going in that direction the magnetic field is going to be in this direction it's going this way it'll be that way yeah make that a 1 make that a zero there's 8192 of those on this plane all right yeah then there's 14 of those planes stack up to make this module this module is what you're holding all this stuff now are the drivers to drive this that's just to program it as a 1 because this is basically an analogue process right I'm not writing ones and zeros into a logic gate and storing them that way you're just actually having to make magnetize a core one way or the other and then I've got to read it and when I read it I destroy the magnetization so I have to turn right back around and then write it back in there so that it's not missing oh no so there's one of these in this and then there's one of these now each one of these blocks on his wall over here got it so we have four eight twelve sixteen thousand words of memory another four eight twelve sixteen thousand words of memory now when a Saturn is flying both of these memories are executing the same flight program completely in parallel that's right and they're comparing the outputs to make sure they're getting the same answer if they were to not get the same answer it's going to subroutine and say I'm at this point in the flight I got these two numbers what makes the most sense to keep using use that number and keep going so your critical parts are triple redundant in the logic dual redundant in the memory as I recall during all the Saturn flights we had like less than 10 miss compare something like that it was a very small number so that you pulled the data down while it was flying if things happen too quick and flight too how do you know you had we get the data back and then we annulled that was my job at IBM as we were ant analyzing the flight data to determine what worked what didn't work if it didn't work on this flight how do we fix it on the next flight and then when you get the NASA requirements for the next flight make sure we got everything in place to do what we are supposed to do so the data tapes come from all around the world through Goddard Space Flight Center is responsible for that so they get us the data and then we analyze it and determine what happened a lot of the work was by today's standards was pretty and crude we would have a something would go wrong in the computer and it always goes wrong when something else is messing up the telemetry system so we would actually get what they call an octal dump we have this 11 by 17 sheet of paper 10 bit octal numbers so you'd have their 4 characters like 0 to 7 size you go with octo arithmetic so you get all these things I think it was like maybe 40 columns and 30 rows something like that so we would get this thing printed out in all it's just numbers well the piece we're looking for is in a particular place down here well the drop out is where we you know telemetry drop out so we would actually get this printed out 11 by 7 fan fold paper spread it down this hallway get down on your hands and knees make a template cut out the you'll have a number of measurements that'll always be the same you know right like a voltage that never changes yeah so we know what those numbers ought to be so we cut the holes out and slide it down page by page hey these are look good okay this frame is probably good so we go find so many columns so many rows same other number we won't write it down so you're looking for one that if it bums up something that you know is a fixed value then it probably bummed up something else that's right and if the fixed value is okay then somewhere in there our number is probably okay and then once you've got the problematic one I mean is that just the world's nastiest Sudoku puzzle or well how do you solve that you you may have you may have to do this for many many many frames then you take it to your desk and take those octal numbers converting the decimal numbers go to a calibration chart and say okay I got this number yeah go up my chart so that means it's 5 degrees centigrade so you write down five degrees you figure out what frame you are that's about what time it is - at this time I hit 5 degrees then you go to the next room now you do this for about two weeks and finally you got enough to prove plot a graph by hand so you put all these numbers in and you plot it by hand and then you say hmm that wasn't the problem after all oh well here we go again so boy this is Edie hi this is the hit I'm sorry this is kind of an in the hand example of the memory course that you can see woven into the spread here and then kind of under the magnification over here and there's about eight or nine of them in there so like Luke was saying when you run the current through there it starts to spin that donut in a particular direction that tells you whether it's the one or the zero and you're saying they were woven on by hand it was primarily women that did the work that had basically a bench top so they would have like textile industry experience I guess or I actually am NOT certain what their qualifications were but they would sit with a bench top with this thing mounted in a holder yeah with copper wire lengths and tweezers and their fingers and a lot more patience than I have to weed these things through there to make sure that they went through appropriately no kinks no bends that were out of a spec and to actually make sure that the little donuts go into across you know the way they should in that we're all uniform so everything would be predictable behavior incredible thin I just wanted you to hold a physical bit mm-hmm you know what that's like yeah yeah I mean this is this is more than eight bits so this is I'm holding at least a bite so when you look at this what what kind of a motion do you feel when you when you look at this loop do you do you are you on this or is it more just thank goodness I don't have to work on that bloody thing anymore no I'm gonna talk to one of my buddies when you go out to build know that that's that's a real piece of work you know and it looks to people to come in here they say this this just looks so much like an antique but again we only had a few failures during the whole flight that were intermittent he never had a catastrophic failure people might say antique but I would say handcrafted yes there's a lot of handwork went into these well you can tell any know even just even even these are these clearly handrail they've got the goop on them because the big problem with this thing is vibration though the memory that we were looking at over there is a hands-on there they test and test and test on that thing to make sure that you hadn't got a kink in the wire or twist because if you do the vibration is going to cause it to break those things were made by hand the ladies actually wove these things like you're weaving a piece of cloth pretty amazing now sixteen thousand words of memory yeah 26 bit words okay and we had two extra bits and that was prepare tea for error-checking got it so actually twenty-eight bit words today everything's 32 bits right now remember every time you add a bit you double the amount of stuff well this thing you look at this and you look at the the core plane and you look at the work that goes into it so you don't want to add anything more than you have to so this thing they realize that 30 26 bits is the biggest data word I'm going to ever have to have to make this mission fly I can take those and split them up into 13 bit syllables and I can use those for data words and that will cover everything I need so you stop at what you need 28 bits you don't go on to 32 because 32 be 2 times 2 times 2 times 2 that many more times 16 times more expensive than this was an unreliability that's the key because the more of these things more cores you add the more of this stuff you need the more unreliability you add to your system because sheer numbers of parts right when you're talking physically assembled parts right you're trying your best to keep the reliability numbers up as high as you can on this thing so the less parts you have the more reliable provided to do this job got it which worked now this computer the digital computer is an outgrowth of what was done on the Titan missile okay this is an outgrowth of a following from what was called the ASC 15 which was a Titan missile computer which IBM had done for them the Titan used a combination digital and analog we did the same thing here this computer controls all the timings start engine stop engine fire separation rockets fire retro rockets all this kind of stuff it does navigation and guidance you have stored in the memory a profile at this point in time I need to be here going this fast going in this direction you have stored where you want to be yeah this thing now is reading the guidance platform information 25 times a second and he's calculating where am I have fast am I going what direction am I going all right computer now he's operating in a big two second major loop they call it and then within that major loop he's getting interrupts to do other things we didn't have an operating system just got this major loop and we're executing over and over and over and over navigation guidance control navigation guidance control interrupts go do something come back navigation guys control interrupts now once they get interrupted to do the switch its interrupted to read the platform the guidance system and say alright I need to twenty five times a second I'm gonna get an interrupt it says go read that platform information and calculate where am I fast I'm going and so forth all right he gets a timed interrupt it says it's time to issue a command down to open the valve in the first stage right all stored in memory he said a little timer he's setting over here said okay I got a next which Lecter must be done at this many seconds from launch he sets a timer counts down to zero look zero I go do this so there's no advanced no scheduler on the CPU itself well that's what is manual like a manual scheduler that's what these switch selector commands are that are stored in memory there the scheduler when that thing interrupts and says go do this switch like and you go do it okay then you come back then they have things like when the stage separates engine shutdown those are all interrupts will start time-based differences and so forth so all of that stuff is is going on continually now the navigation is cut the stored profile that's where should I be he's read the platform informations done the computation yeah here's where I am I'm comparing where I am versus where should I be that's navigation turn turn turn plus the era hands it over to the goddess routine the guidance routine says what's the best way to get from where I am to where I should be in the next two seconds my major loop so he turns he returns with the guidance comes out of the goddess things and say I gotta make this correction now it's time to wiggle some engines to get me to where I'm supposed to be he sands that command over to this thing that looks like a barrel that's an analog computer ok now this thing takes a set of rate gyroscopes inputs that are another set of gyroscopes besides the platform guided system and it's measuring how this vehicle is moving physically all right each axis so they're feeding into this now this thing takes this command from the digital computer says I need to make this amount of Correction he looks at the rate gyro said well this guy wants me to make this kind of Correction but I'm already moving in that direction so I don't have to make that much or I'm going in the wrong direction I got to make a whole lot and then he in turn sends a command down to move an engine now when we create a gyro scope in a modern phone for example we basically just print we just print on to onto a circuit board like it's it's hardly it's it's tiny now this that's a piezoelectric transducer these are these are spinning mask wheels these are live scopes or spinning mask just like your toy gyroscope you had as a kid and so whereas they cost a million dollars apiece instead of a dollar 95 and so because it's an analog computer taking actually moving spinning no no no no this computer has been reading this the gyroscope that one's reading it remains the main platform system this one's reading another set of gyroscopes the gyroscope now just outputs hey I'm moving this much in this axis X Y Z God then how do we read that is it a voltage output or these were voltages the ones that this reading were pulses got it he actually gets a pulse every time he gets point over 5 G's of acceleration he gets a pulse got it so the computer now is summing these pulses to determine what his current velocity is the integrating acceleration gives him blood so at that time tell me what was more accurate this one or the digital system what was more granular the those are a lot more accurate than this yeah got it the problem of this is when you're trying to calculate a long term flight all right the problem is drift gyroscopes have friction friction causes the gyro to move any motion in the gyro is picked up as physical motion for to fly this thing you have to have a much more accurate gyroscope in the guidance system that you did in the rate system great no not quite as accurate got it did you count for gyroscopic precession as well yeah how to do that's all it takes you how to do that before the flight that's all accounted for and in the in the process and the program then you test and test and test and test that's how you do it you test these poor machines until they're just about worn out and then you take them to the middle right so flight control computer the analog computer actually sends the command down to move the engine now remember we said we're in a major loop two seconds so he's going to send the command down to moving engine and there's gonna be two seconds before he gets another command to wiggle that engine anymore they gonna move a little bit and a little while later gonna move a little bit take for example the first stage those engines are so big and powerful that when you move it you move the rocket but you also induce flexure Mo's bending modes the poor astronauts are sitting up there in the spacecraft three hundred and some-odd feet away they're really feeling this we asked one of them said what did it feel like when this thing is flying he says it feels like you're riding a train on a bad track and that's because you're getting these every two seconds right you're about to see Linus get very interested in the thermal system of this computer if you've seen this channel you know he's tried to liquid cool everything so the questions he's about to ask Luke are from a modern computing perspective but he's trying to put it in historical context and Luke is providing that historical context so this is a fascinating exchange for me I enjoy this all right computer basically the instrument is divided up into three pieces you start about here and you're going up to the flight control computer there and that's pretty much your navigation right here that's pretty much your navigation God's control section so about a third of the ring or so yep then the top part up there that's mostly your telemetry packages and then down over here we have the umbilical plate then we have the environmental control system and we have the three big batteries there the water supply for the cooling system and then these are auxilary and main power distributors for the system so this is sort of your environmental power system and that's kind of waste divided up the plates sort of goldish looking but he tries those we're pumping their aluminum you pumping Kuhn it's anodized aluminum through there to cool the components each component each plate would dissipate about 420 watts that's how you're cooling the equipment some of the equipment like this platform here and the computer actually we usually plumbing it directly and there's passageways inside the unit we have the same thing in the digital computer and in the analog computer now what I don't actually see is where you dissipate the heat too because that little box up there there's got a little gray box it has the two plates with writing on it yeah it's called a sublimator iSuppli meter that's how you dissipate the heat okay so that's essentially a sublimator there's a box just conceptually how it works it's a little more complicated but fundamentally so you have a box you have a tube coming in and has the coolant in it just say a cola tubing going through that box and out the other side yeah all right the plate now that has the writing remove those plates before launch say they've got tiny holes and then pours very microscopic once you get out of the atmosphere then you open the valve and this thing the other thing that looks like a barrel is full of water and then has a bladder in there so it forces it fills the sublimated with water each other's little pores forms a plug of ice that ice now Sublime's goes from solid ice to vapor and that's cooling it it's how you cool the astronauts when they do an e VA they have a small sublimator on the back of their backpack and they have underwear that has tubing and they're pumping coolant through that tubing that will dissipate 9,000 watts that's pretty amazing little gadget so forgive my stupid question but a typical air conditioner works on phase to phase change cooling concept there you go from liquid to gas and gas to liquid and use the compressor right we don't have to have a compressor with it you have no compressor you've got a couple of pumps in that right above that single battery by itself goes to there coolant pumps you just have to circulate the cooler but you don't you're not pressurized it's not a refrigeration cycle huh it's magic it's not magic that's pretty good that's pretty good cut point to that thermodynamic first and second law just put into action okay so what freezes the water in the micro porous well you're exposed to faint space out here and you got pressure down here and this it's a it's a Porsche you know what centered metal is actually yes okay okay this is centered metal so you have tiny passageways through there and it's making it makes its way through and here I'm exposed to space and I've got water pressure down here now form a plug of ice and that little plug of ice goes directly from ice to vapor just like you're sweating because we actually do vapor right and that's because we have the benefit of the battery so does that work during the first part of the lunch not at all what I said you got a way to get out of the atmosphere out completely or at the edges pretty much out pretty much out about 180 seconds that's the third stage is about just started to burn nothing but you've got enough water in your reservoir that you can absorb the heat while you're making your way through yeah it only went through a couple of cycles during the boost phase once you get out into once the crew separates yeah that's the biggest problem because we start getting sunlight in here and things get hot pretty quick and it really starts cycling on and off pretty fast the basically the coolant temperature is cycled between 50 degrees and 60 degrees you get above 60 degrees the computer sends a command says open the valve fill it with water and then it revives it on back down and gets down to 50 closes of the valve and it'll start heating back up and it just slowly cycles back now you can only carry very small amount of water oh we got a last 11 12 hours that's when the batteries run down so that's plenty of water in there you remember all this it's unbelievable now according to him it's simple I just make it serious like I've worked on systems like a couple years ago and I don't remember him to the level of detail that you remember this yeah this was this was quite a system really um okay so can you tell me about the spherical one is that this okay that's this yeah that's your platform redundant or what are we looking at the platform all right you asked about the gyroscopes yeah the gyroscopes are spinning mass just like it's spinning well don't know no I'll show you there in a minute okay you basically have a spinning wheel yeah motor driven okay instead of having ball bearings are bearing is gaseous nitrogen it's floating in nitrogen trying to get that right that friction down to get those drift rates as low as possible can I ask another dumb question if you if you want as little drift as possible why nitrogen why not helium why not a nitrogen is a lot cheaper so there were still cost constraints yeah well what we've got here is a is a system remember we said the computer came out of the Titan well these came out of the Jupiter programs okay okay purging Saturn and so there was no real need to go to anything that drastic for the short duration mission we have if you had an extremely long mission that's a different story God and Skylab we were nine-month mission so we actually used rate gyroscopes and used navigation updates using Sun sensors and star trackers and that kind of stuff to periodically zero us back to where we were long-duration you got to take a lot more steps than you do here this is a short-duration mission got it we only had to be accurate for six minutes nine minutes 11 minutes to get to orbit another six minutes to get from orbit into the trans lunar trajectory those of the so very short time so the nitrogen is supplied by the sphere electronics and visiting a tree three blocks from here so this is just as much just compressed gas ball right and then 3,000 psi and these are just regulators okay if you did this today you wouldn't use that this would probably be a ring laser gyro electronics you wouldn't need that probably all fit in this box right you go to a 747 that's probably the batch size box they'd be using got it now can you I mean this might not be your specialty but can you tell me anything about the cabling here is this fiber optic is it copper that's known as wires just plain old wires we hadn't when we did this fiber optics sending been thought of yet got it okay so just plain wiring most of the as I recall I think the the installation is probably teflon these now are coaxial cables here we had some other coaxial cables that ran around this that were more long like what you might see for a cable TV on the pole with actually had aluminum outer tube polyethylene dielectric and then the center conductor was copper and that would be going from this CC s transponder up to the antennas for the long runs Oh sort of runs they just use RG coax okay so sorry this is going up to an antenna for what is that okay yeah this this system has several pieces of telemetry the ones up top up there VHF we had UHF telemetry on the early versions these were VHF and then this was s band 2200 megahertz 2282 I believe it was this is transponder this is a power amplifier and this is a coaxial switch we had two hot had a high gain antenna a low gain antenna and two omnidirectional antennas for the high gain low gain you got a point position one toward the ground yeah so that you can pick it up the Omni you don't care where you know we pick them up but the signal is a lot weaker right okay so this thing now with telemeter primarily the computer telemetry we talked about with the big sheets of paper nocturnal dumps so this one transponder would primarily do that but it also had the command system so you can send the command up when you get into orbit during during boost you can't do anything things are happening too fast it's coming so once you get into orbit Houston can say well you know we need to recirculate some something in the s4b stage so they can send the command to the lvdc through this okay through this sends it to the lvdc and they'll execute whatever they tell it to do and update your you can do nav update you can do a lot of things through the command system so this is both deals the other thing is on the later missions from 13 to 17 we actually would crash the third stage and the instrument unit they stay stuck together they know you know once they're made it to Cape they're mated for life they never separate so we crash those into the moon yeah and we use this transponder we added an extra battery so that we could track this transponder all the way to the moon and when it went when it quit then we knew we'd hit the moon and they could take that and correlate with their seismometer data yeah that's for me an instrument unit hitting the moon is about equivalent of 11 tons of TNT it would produce about a two-and-a-half-hour moonquake oh wow yeah so you would use blue this is the Laura he died that's t 0 for impact and then you would compare that to the RF for the seismometer on the on the moon yep and that's how you know it was a two-and-a-half-hour moon well the size monitor just kept on for two and a half hours yeah before that side seismometers pretty quiet no too much you get small quakes you always have a little bit of Rumble on the moon I can see the little green men running out running around you oh my god the Americans are back you don't have to put that yeah the reason for that one of the science objectives on Apollo was to determine if the moon had a molten core god I doing this experiment they hope to take that telemeter data the seismometers yeah and determine originally the data was very noisy very difficult to determine about six or seven eight years ago I don't remember exactly how long group out here at Marshall dr. Renee Weber planetary sciences group they took that old data cleaned it up with modern signal processing techniques and determined sure enough the moon does have a liquid core you can go out on the internet and they've got it she has a diagram that shows this concentrated iron mass in the center just like the earth has another layer of molten around that it has a layer that's not quite solid yet and the moon is slowly cooling over time oh this is fascinating thank you very much by the way hey thanks for watching a thirty minute video on the second channel hear you clearly kind of get how my brain works this is a more in-depth looked at how this stuff works and you clearly are a pretty smart person that likes this stuff so I think you might also find this interesting this was on loan to me from a guy named Mark he has a website called rocket relics org I think you'll like that I mean if you're watching a thirty minute video you're into this stuff big thanks to Mark for letting me borrow that stuff thanks to you for watching this if you feel like this added value to your life consider subscribing and maybe even ring in that Bell to be notified when something comes out here on the second channel thanks everybody that supports smarter every day on patreon thanks to Linus for doing this with me he's got a video you can go check out yeah I guess that's it thanks for sticking around you're pretty awesome I'll give you a fist bump on the way out I'm Destin you're getting smarter every day have a good one

Channel: Smarter Every Day 2

Views: 2,160,998

Rating: 4.9413776 out of 5

Keywords: smarter every day, apollo, nasa, moon landing, destin sandlin, moon, rocket, engineering, computer, linus tech tips, linus, linus sebastian

Id: 6mMK6iSZsAs

Length: 44min 30sec (2670 seconds)

Published: Wed Aug 07 2019

Reddit Comments

[u/DarrelCanada]

I admire the level of humility and respect Destin gives to the people he meets. His open minded approach to science paired with a clear faith in God and priority for family is a good model for 21st century Christianity. He is not at all preachy, but instead exudes joy for life and learning which I believe comes from a passion for a deeper understanding of creation and its Creator. From the first videos I watched on his YouTube channel, Smarter Every Day, I desired the same sense of child like curiosity backed by a PhD level education. Destin Sandlin for President!

[u/andicav]

Amazing. So glad I watched this. Interesting bunch.

[u/agumonkey]

Luke Talley is such a perfect interviewee, smooth, relaxed, precise.. As Destin said, the breadth of his knowledge is mind boggling and he just spills it like breakfast time chat.