We fix the glitch in the crystal oscillator here: kzread.info/dash/bejne/k5hsw9yHn9nZdps.html And we make it atomically precise here: kzread.info/dash/bejne/jJaFk8Gsh5zge5s.html

@davidwagner6116

2 жыл бұрын

Thanks!

You know your life has gone right somewhere when you can expect one of your friends to just "show up" with a caesium clock

@markfacca

4 жыл бұрын

Exactly!!

@staglomagnifico5711

4 жыл бұрын

@Molloo3 I don't know, those things are pretty expensive...

@isettech

4 жыл бұрын

Using that non crystal oven oscillator with digital inverters, should place this accuracy somewhere about the same as a typical quartz wall clock. Hope the crystal is T cut for long term stability.

@alexlandherr

2 жыл бұрын

I (figuratively) can’t wait for the day where there is a cheap enough HAT with a Rubidium CSAC for SBCs like the Raspberry Pi.

Give a man a clock and he knows the time. Give a man two or more clocks and he will forever doubt his concept of what the right time is :-)

@leyasep5919

4 жыл бұрын

oh, I see, another Time Nut here ;-)

@AndyHullMcPenguin

4 жыл бұрын

"Give a man a clock and he knows the time. Give a man two or more clocks and he will forever doubt his concept of what the right time is :-) " Give a man twp clocks, and within a few short months, he will have collected a whole bunch more. Clocks are like multimeters, you can never have too many of them.

@leyasep5919

4 жыл бұрын

@@AndyHullMcPenguin just like Tektronix scopes

@pankeaux

4 жыл бұрын

give man a fish...ummh...

@leyasep5919

4 жыл бұрын

@@pankeaux teach him to fish and he'll build a fishery so he can afford an cesium clock

This clock was a replacement of a mechanical one. So I suspect it was an improvement.

@CuriousMarc

4 жыл бұрын

We thought this might indeed be where the origin of the 30s/day spec comes from.

@lwilton

4 жыл бұрын

@@CuriousMarc 30 sec/day = 350ppm. Not real good by crystal standards, but over temperature maybe reasonable.

@stevew8233

4 жыл бұрын

@@lwilton 30 sec/day is not even great by mechanical wristwatch standards. 4 sec/day is within traditional wristwatch chronometer standards, as long as it is maintainable over a number of positions and temperatures.

@Eo_Tunun

4 жыл бұрын

I guess even sixty years ago, any customer of a watchmaker would have returned an up-market wristwatch that was this bad at keeping its time. In the nineteenth century, there were wooden clocks that aberated by a minute in 4 weeks! The only way I see the Soviet space program would be happy with a clock this unprecise is if they built it for a certain procedure of use from the start, where it only had to run for short terms, countdowns and their likes.

@Smertyuk

4 жыл бұрын

@@Eo_Tunun IIRC this clock doesn't send any signals out other than its timer's relay, so its purpose is mostly UI rather than control, baring any abnormal procedures, like manual deorbit burns etc. The ship does have a digital computer, which is what probably provides external clock for the thing.

Boeing should buy one of these for Starliner, it's way more accurate. Their clock was 11 hours out.

@petergorelov418

4 жыл бұрын

Ken Shirriff is much better an investment ;)

@peeedurr

4 жыл бұрын

Oooo, cutting; but nice!

@johndododoe1411

Жыл бұрын

User error, the astronaut hit the clock reset button during launch. Not MD's problem. Tell FAA to revoke the guys pilot license. Let's check his name ... Mr. U. Nmann. Ed. Damned foreigners...

This is one of the few channels on YT where I press the like button before I see the clip, because I know it's going to be educational, entertaining and inspiring, and I don't want to forget to 'like' it.

@seedschi

4 жыл бұрын

doing absolutely the same!

@964cuplove

4 жыл бұрын

Like Greg’s airplanes

@paulromsky9527

Жыл бұрын

I did too!

Now to buy and recondition a used Soyuz spacecraft to build around the clock.

@LordAlacorn

4 жыл бұрын

Then buy and recondition rocket around it. ;)

@AKWoland

4 жыл бұрын

@@LordAlacorn After that: but everything has begun just from the clock! :D

Your American colleague reverse engineering that clock...Genius!

@jorgeszabo1659

4 жыл бұрын

Damn Western spies

@grubboy3514

4 жыл бұрын

@@azzajohnson2123 Wow...Just watched that video. He's some kind of genius for sure. Subbed to his channel now.

I know next to nothing about electronics, but a fair bit about mechanical engineering and spaceflight, this channel is beyond fascinating.

I know very very little about electronics, but I still enjoy the content your team makes. Have always been interested in this stuff. Excellent channel, excellent presentation, keep up the good work!

Awesome keep up the good work. I look forward to more videos from you!

I deeply envy your fancy tech nerd clubhouse. :-)

Looking forward to the next video :)

Props to Ken for the reverse engineering! And Mike is back, whohoo!

Amazing ! Please want more videos!

The things that you guys can do blows my mind.

Would love to see a little complete tour of your basement/collection/lab, as always and expecially for the series of space releted clocks computer this is an extremely interesting video

When I worked at Boeing we would call the overengineered Apollo clock a "science project". People would sometimes get annoyed when some of us would insist on perfection rather than just "in-spec". I admit I'm guilty as charged of being a perfectionist on several occasions **wink**.

Why do I find this so fascinating!

My work order when watching your videos: Open the video, Click the like button, Watch the video. The things you are working on are very impressive.

The gang back together at 9 minutes is so nice!

Great vid... again

Mike is back! I see more AGC videos in our near future :-)

Oh my, I thought you were done with the clock. Cannot wait for the upcoming episodes.

@leyasep5919

4 жыл бұрын

muahahahahaha ! You're NEVER done with a clock, you naive mortal ;-)

.....I hardly understand the details, but it makes me want to instantly come over and hang around with you guys! Introverts Unite!

Hi Guys, just when I think ah the Soyuz clock will be boring enter Mike and compare it to the AGC in language that even I can understand! This channel is sooo good even for a non technical person like me! And Marc, you have time for a wife? She has to make an appearance to explain what she’s doing while you’re enthralling us with Soyuz clocks and the AGC! Seriously guys, thanks for sharing. The Paleo biology episode were fascinating. Keep them coming. Cheers from Australia!

My old Russian railroad pocket watch keeps better time than the internal oscillator and almost as good at the 4 seconds on external. You do very well explaining technical details in a way that those new to electronics can understand, while not boring those of us with years in the electronics industry. You guys do great work, keep it up!

This was suggested - I have no idea what's going on but I like all the cool electronics & blinky lights

Looks like there is some issue with the oscillator. I have dealt with many devices having the similar oscillator design with a pretty stable non-glitching output. Soviet 74xx-compatible logic ICs tend to degrade over time due to ageing and environment temperature changes. For example I have seen dozens of retro devices stop working after a long period of storage (mostly in random conditions) just because of dead 7404/74LS04 inverters.

@VandalIO

2 жыл бұрын

This would be Soviet satellite grade logic ics maybe equivalent to 54ls

Great video CM Plz do more crt videos no matter the problem and or age

When my watch loses one minute per day: eh it's fine When a clock from the seventies loses 4.2 seconds per day: Pathetic

I just spend a day poking with a scope at jittery soviet logic (that has that "logic used as analog" thing going and "analog used as logic" on top). So it's nice to watch someone else do it.

Great video once again. Interested to see if this is a failing part.

And thanks for the nice video :)

Their electronic equipment must have added a considerable amount of weight to the spacecraft. The combined mass and volume of all of their equipment must have significantly impeded the flight capabilities of the ships that were so equipped. I love watching your videos. Keep up the he good work.

I approve the theme song from the Spectrum Holobyte's Tetris for Mac!

Could you please go into some detail on the timing requirements of space flight. How do error in both drift and having an accurate clock effect navigation. Also what kinda of errors you can expect being of in both parameters by 1 second, 10 seconds etc? thanks again for making such informative yet laid back videos! I have learned tons about the fundamentals of computer science watching your channel.

@gu4xinim

4 жыл бұрын

Surprisingly close to what old ships would use for navigation, time and stars. By knowing what time is at source location (Houston or London, for example) you could in the middle of space and/or the ocean use the stars, with a sextant, to compare the difference of what the sky should be and know roughly where you are. In the case of the spacecraft you have a clear view and waaay more reference points to look at. Of course some limitations apply, it was used to get some variables in orbit and attitude while on route to the moon. A search for Apollo sextant navigation will give you a lot of pretty cool information about it.

@davidmcgill1000

4 жыл бұрын

Not that it would come up in standard space flights but time dilation is also worth considering. Eventually the on-board clock will have to get synced to a clock on Earth's surface even if it kept perfect time.

@rayg9069

4 жыл бұрын

@@gu4xinim Just trying to comprehend the 3D mathematics involved to find where you are in X,Y,Z axis' while traveling at 1,000s of Mph makes my head hurt. Those early space engineers, of all disciplines, were beyond brilliant.

Looks just like the oscillator circuit of the TRS-80 computers. I'm amazed that y'all could reverse-engineer that thing! Now we need a T-shirt of it.

@CuriousMarc

4 жыл бұрын

T-Shirt is in the making

Start at the Crystal and follow the signal train on scope until you find the glitch source component. Not like your going to find a replacement ? That jitter will not clean up using the Trigger Level ?

You surely know how to keep the tension... so much in the pipeline: The bad clock timing, a caesium reference, a missile control computer aaand the team is complete again! Did I mention that I don't like cliffhangers? ;-)

Those glitches are the alien world trying to interact with Jodie Foster in the movie CONTACT, har!

@CuriousMarc

4 жыл бұрын

Finally an explanation that makes sense!

@JohnBoyDeere

4 жыл бұрын

@@CuriousMarc Love the vids especially the AGC series of which I forwarded to a few real computer "nerds" that thoroughly enjoyed every moment, thanks!

With friends like that you are never alone

You guys are totally amazing! I mean, I can reverse engineer machines and mechanical devices and even fabricate parts, but the field of electronics is like alchemy to me! I also liked it better when the US was frenemies with the Soviet Union, not at war by proxy!

That cliffhanger :O

I've seen nearly that exact "hiccup" before but in a function generator... I suspected it had something to do with the digital portion of the generator, like an edge case where the execution loop period is super close to a harmonic of the waveform being generated. In my case I was able to ignore it.

I would love to see ALL the pins of the double NAND-gate oscillator circuit probed. Also including the power pin. I can't figure out how that high-frequency glitch would arise from the capacitor coupled feedback circuit. I bet it must be external, such as from the power/ground circuit.

Are their any hires photos, dimensions and other info available online for this clock?? I would like to make a working model of it one day....

Makes you want to measure the interval of the glitch. Noise from the power supply? But the digital divide by 10 ic's clean up the glitch.

This was not a spacecraft's main clock. As it fits into a slot previously occupied by mechanical clock, it's for crew reference only. Flight instructions and procedures involving this clock don't require any higher precision than that of a wristwatch of 70's era when this spacecraft was originally designed.

What is soldering wire do you use? So shiny. Thank you.

I suppose intervening by scope probe on oscillator elements is matter of glitch. Capacity of probe cause of parasite oscillation. When measurement done on 1 sec pin you got clear output.

@SeanBZA

4 жыл бұрын

More likely noise on the power supply pins, probably caused by either a set of counters rolling over, or by a external drive, and insufficient or failing board decoupling capacitors. You could probably get the capacitors as NOS as well, there are plenty of them on eBay, or as part of old Soviet era equipment being sold there as well.

@InductorMan

4 жыл бұрын

That's my vote as well. Excessive probe ground conductor impedance would allow any switchmode power supply frequency ground current flowing between the instrumentation and the clock to impose an external disturbance on the circuit. It would be easy enough to measure the 1Hz signal both with and without the 1MHz probe in place and see if the 1MHz probe is disturbing the oscillator.

@rayg9069

4 жыл бұрын

If they were measuring on raw oscillator signal for sure capacitance of the probe could be a problem, if they were on a buffered 1MHz it should have been okay.

@ethanpoole3443

4 жыл бұрын

Ray G The output they were measuring should indeed be buffered (and assuming they used 10x mode on their probes then there would by 9-10Megohms resistance in series with a capacitance of perhaps a few tens of picofarads. That would be enough to potentially pull an unbuffered crystal slightly off frequency but is rarely enough to significantly interfere with its output in my experience, and in the case of a buffered output the load and capacitance are so slight that they should not affect anything. That said, if the probes were introducing enough capacitance for it to distort the signal to the point of glitching then one would have expected to see signs of excessive capacitance on the scope display where we only saw modest effects of capacitance but an otherwise acceptable squarewave barring the intermittently glitching output. My guess is possibly a failing bypass capacitor nearby allowing the rails to momentarily dip severely periodically due to a much larger load switching on/off elsewhere in the circuit on the shared power rail. However, they could have likely worked around the glitching as the scope captured waveform showed that the glitches typically had a sufficiently lower peak voltage that adjusting the gate level on the counters should have been sufficient to avoid counting the glitches since the glitches otherwise only skewed the duty cycle of the neighboring waveform but not its averaged period.

Is the glitch still present when the case is reinstalled, if you sample after the first divider? Perhaps the scope ground lead is causing local EMI to couple into the sensitive oscillator feedback network? Is there an asynchronous display multiplexer clock running at the glitch frequency?

@d.jeffdionne6139

4 жыл бұрын

Ken's schematic shows a buffer amp (inverter) after the oscillator, but it looks like it's in the same package. Still, I suspect the probing was injecting noise, and is the cause of the glitching.

Its got a timer - could you have hooked into that switchable output? (written @ 2 minutes in - incase you do that later)

Put another scope channel on the power supply pin of the oscillator chip. I expect you will see the power is being glitched synchronously with the spikes you’re seeing in the clock output. Probably due to something in the first divider. TTL oscillators of similar design are not that bad. They are ubiquitous in microprocessor clocks of the 70’s and 80’s.

I repair wristwatches and clocks, mechanical, quartz or transistorized, and I can't wrap my head around this thing. It's so much more complicated than it should be.

@leyasep5919

4 жыл бұрын

I totally agree ! but, hey, Soyouz !!!

@guywilkinson

4 жыл бұрын

Maybe true but depends on an FMCEA & reliability analysis, I like the way that it uses individual decoders for each digit, so it still works for other digits rather than not at all.

@rayg9069

4 жыл бұрын

It's just as complicated as it needed to be for the technology of the day. It's not every clock that you can fault find down to individual display segment driver gates. This technology is one step on from discrete diode transistor logic. It's a thing of beauty, when engineers understood to gate level how chips worked.

Analog electronics is freakin amazing

Those pulses on the 5v rail from the last video, right?

At @6:50 you say "that's a tricky circuit, because it is an analog circuit made with logic parts". Well.. it might be tricky but it is absolutely common to do it this way. Search for "images Xtal 7404" in the interwebs.

@CuriousMarc

4 жыл бұрын

Very common circuit. One of the most basic ways to make a quartz oscillator out of a few spare logic gates. But certainly not known nor used for its accuracy. To make it precise or to temperature compensate it, you’d need very intimate knowledge of the analog behavior of the digital gates, which is why I called it tricky. I was very surprised to find it there. I expected at least a TCXO.

12:39: The components were not single-use, but single-source?

i dont track it since the begining, so whats the story about this? how someone can get access to documents like that?

You're getting too good at cliffhangers...

6:40 - the gate time of the 2 meters should be in sync in order to capture the same, longer gate time = less time out of sync out of the total measure time.

@johndododoe1411

Жыл бұрын

The meters don't gate their inputs from any clock, they convert the input to logic level and analyze the result. Disagreement between them is how many of the small glitches are tall enough to count as genuine GHz pulses. Measuring the output from the on board divider will use whatever the clock uses for that decision.

Great video! WOW! The accuracy was only 4 seconds a Day with all that hardware! Just about any digital wrist watch at the time was accurate to 7 seconds a YEAR! Maybe the 1 MHz clock circuit has a "walking wounded" gate in it... its works but glitches. See if you can clean it up with some decoupling caps. I would have NEVER let a design out the door with a glitchy clock, especially when lives are a stake. I saw in your prior video that the 5VDC supply is very noisy.... it must be due to age.... how would they ever go into space with that! Yes, I agree, there is way too little decoupling capacitors in the digital circuitry.... now that is just a poor design and can't be attributed to old components going flaky over time. Space Shuttle or not, I would never go up in a Soyuz capsule.

Does the team have individual youtube channels?

That jitter might be an intentional effort to extend the average period by 1.2%. I assume the crystal is in a temperature controlled oven to stabilize its frequency. Evidently this results in a stable frequency that is 1.2% above 1 MHz. Knowing this and stretching one period by ~30% at reasonably regular intervals would restore the average frequency to 1 MHz. Since crystal frequencies vary some this might be an effective calibration strategy. Since divide by 10 counters and 1 MHz crystals are common and cheap, this would be cost-effective and timely.

Hi Marc, thanks for this great Job. Plese put here or post the NASA (APOLLO) documents used in this video.

@CuriousMarc

11 ай бұрын

Links in the video description. All of the NASA documents we use are uploaded, you can start with the master list here: www.ibiblio.org/apollo/links2.html Credit goes to Ron Bukley and Mike Stewart for many, many years spent researching and scanning all these in

In Britain you can use BBC R4 LW on 192kHz as a frequency standard as the frequency is set by an atomic clock.

@sakadabara

4 жыл бұрын

I think Britain is in postBrexit war with France now

Maybe that is resetting every now and again? Looked like a regular interval, leave it on for a day?

По результатам испытаний получилось, что Часы Союза имею точность 0,005% (уход на 4,3 секунды за сутки), при этом точность блока генератора импульсов Apollon имеет точность в 100...300 раз лучше. Сравнения некорректные! И вот почему: 1. измерения точности часов Союза проводились с РАЗОБРАННЫМ корпусом (нарушен тепловой режим кварца). Работа же подразумевает определенную стабильную температуру кварца. 2. На блок кварца при открытом корпусе попадали дополнительные импулсьные помехи. Корпус металлический и является своего рода электрическим экраном Т.е. испытания нужно было проводить с ЗАКРЫТЫМ корпусом 3. При проверке точности следует предварительно ПРОГРЕТЬ устройство (15..30 минут) Во всяком случае в инструкции на аналогичный прибор Appolon записано что требуется предварительный 15-й прогрев, чтобы прибор обеспечил заданную точность. 4. Блок генератора импульсов с Appolon имеет совершенно другую весовую категорию. Это специальный термостабилизированный генератор импульсов для компьютерной системы. Блок питания таймера Appolon вынесен в другой изолированный блок Часы с Союза - это просто часы для индикации времени, к которым ниже технические требования: - потому в конструкции нет блока термостабилизации кварца. - импульсный блок питания расположен в одном блоке с кварцевым генератором. 5. Измерения часов Союза должны проводится при ИСПРАВНОМ устройстве. Вы же запустили устройство спустя 40 лет, как истек срок гарантии. При этом сразу видите точность 0,005% и сравниваете не с реальными часами Appolon (которым тоже 40 лет как они пролежали на полке), а технической ДОКУМЕТАЦИЕЙ. Это не одно и то же. Для начала нужно хотя бы проверить "стерильность" напряжения питания (отсутствие "иголок" и других помех на шине питания блока кварца) Думаю, что в технической документации на часы СОЮЗ будет записана точность ухода не более 0,5...1 секунда в сутки. Если бы была нужна более высокая точность, тогда в конструкцию добавили блок парафиновой ванны для термостабилизации кварца. Но здесь этого нет. Кварц часов СОЮЗ стоит "голый" на плате. Те изначально не ставилась задача обеспечения высокой точности генератора. В любом случае, авторам - огромное спасибо за проделанную работу !!!

Let me guess, on the sale listing it was "slightly used"... lol Maybe because it was glitchy is why it was taken out of service?

Lunokhod rover travelled well.

Was the 30sec/day spec over the operational temperature? Your 4sec/day measurement was at a fixed, room temp obviously.

@CuriousMarc

4 жыл бұрын

I'd have to confirm with Ken, but I suppose the 30s is over 0C-70C. Which as you rightly point out is a whole different ball game than room temp.

The main mode is to have sync clocking from the main ship's computer. All space ship devices should follow exactly the same sync clocking. With such approach even some accumulated error in main "sync" module is not that dangerous comparing to the situation when each device follows its own clocks. This autonomous mode is not a main mode, it's sort of backup if something has happened to main ship's computer, e.g. temporal bloackout or it's rebooting( few secs max) -- you still need some cloks for spaceship crew. It's impossible to accumulate even 1s error in such short terms. Regarding this weird osciloscope reading -- no Space radiation can compare to "baba Galia" handing of the devices inside your warehouse. I doubt this clocks were kept for all the time in requested environmental condititions. Actually the fact they were handled to auction and than transfered via regular delivery service to you means storage and handling conditions are already violated. You can't expect it to work with the same quality and accuracy like it used to be during their prime in Soviet Union. P.S. Thanks for the video. :)

My 1980's digial alarm clock is still working, and is much simpler!

And here I thought that they will just let it run for a day and compare it against network time. Boy was I wrong.

@ethanpoole3443

4 жыл бұрын

Even after a day you would not be able to detect even a 10ppm error based on a per-second display on the unit as there are only 86,400 seconds to a day. Measuring the clock source you can attain extreme accuracy in fairly short order and even greater accuracy over a period of time (for example, on a scope display two nearly synchronized time sources, one locally generated of known precise frequency, such as an atomic standard, and the other the source to be measured, and you can time how long it takes for the source to drift out of phase by a given degree and from that calculate the error even without a frequency counter....a frequency counter with a very accurate timebase is simply easier and faster still).

By no means am I even close to Ken’s level but I feel like I’m the software version of him. But in my case I read way more than I write. Ken’s also a National treasure.

With the initial 1MHz measurement were you measuring a buffered signal?

@CuriousMarc

4 жыл бұрын

Yes. We probed the output of after the buffer gate after the oscillator that you can see on the hand drawn schematic.

If I was following when you were scrolling the scope, it looks like there was a glitch about every 20 microseconds. I'm not sure how you might get that out of a div 10 chain, but it seems suspicious. Be interesting to find out what that blue trace is with the ringing on it.

@user2C47

4 жыл бұрын

I would guess the power supply or the display multiplexer.

What is the music at the beginning? 00:04 ??? Edit: found it; Polyusha Polye

@devrim-oguz

4 жыл бұрын

I still can't find which version it is though...

@CuriousMarc

4 жыл бұрын

Look at Episode 2...

@devrim-oguz

4 жыл бұрын

@@CuriousMarc oh thank god... I've been looking for that version for a very long time. I actually watched that episode but somehow completely forgot that it came from that game. Thanks for your comment, I just saw it now because I had no notifications before.

@CuriousMarc

4 жыл бұрын

@@devrim-oguz For those who are still wondering, it’s the electronic version from the vintage Tetris game on the classic Mac...

@LeKudesnitsa

3 жыл бұрын

* polyushko

4 seconds per day is about the order of magniture of a good mechanical watch movement. So if it were to be used standalone, I suspect they would have used a simple mechanical watch instead which was already on the cosmonauts' wrist.

Your clock is running at +57 ppm. A basic oscillator like you have there would ordinarily be around +/- 30 ppm, however this one is decades old, so the quartz crystal has been subject to that much aging, as have all the other components in the oscillator circuit. Also, you don't know the history of this unit in terms of thermal and physical shock. Quartz crystals are pretty delicate. Oscillator circuits are very high impedance, so it's easy to inject noise, and I think that's what's happening when you probe the 1 MHz signal and see the glitch. You seem to have figured this out by the end of the video.

If you can’t set the clock very accurately, maybe there was no foreseen requirement for better day to day accuracy. It seems to me that the real purpose was to measure relatively short intervals of rocket motor burns. Let’s say you plan a burn 20 minutes from now lasting 12 seconds plus or minus 0.1 second. This clock would be entirely capable of doing that. I wonder what the purpose of NASA’s requirements. You do not plan a burn down to milliseconds for multiple days after launch. The start time and length of any given burn is recalculated just prior to the burn given updated position and velocity data from either tracking or inertial reference input. The burn control technology, turning on and off fuel and oxidizer valves, was probably only able to control the length of the burn down to 0.1 seconds, and I suspect worse than that. Why do I need micro second accuracy? Although I am impressed with your frequency counting technology, why not just run it for a day or a week and compare the time with either WWV or a GPS time read out. I find the time on my iPhone to be perfectly in sync with my GPS receiver, and it is readily available. I am a big fan of your very cool videos. Charlie

@Chriva

4 жыл бұрын

I guess they needed the accuracy for navigation? :)

@XMarkxyz

4 жыл бұрын

Consider also that a Soyuz rocket reaches orbit in 9 minutes from lift-off, and it's the most time of continuous engine usage; other manouvers which are for the most part impulsive burns takes only a few seconds so you need a quite precise clock but at least the error doesen't add up so much

"oh so its just a simple oscillator"

Is poor accuracy due to the age and storage conditions, bad treatment when others attempted to power it?

@fungames24

4 жыл бұрын

Unlikely. Soviet engineering did not require high precision. The imprecise ak47 is in use to this day. Was their clock good enough for the job? The answer is yes. Anything else is irrelevant. I suppose, you could point to their just-good-enough philosophy and bad mouth them. I don't think you can truly defeat people through bad mouthing.

@larryscott3982

4 жыл бұрын

FunGames I wasn’t bad mouthing them. I had assumed it was far superior to its current performance when it was produced. So now I will re-assess and figure it was just good enough. The over top engineering wasn’t for performance, but reliability. But making it more complicated doesn’t lend itself to reliable. So I assumed it was engineered for performance.

@fungames24

4 жыл бұрын

@@larryscott3982 I wasn't accusing you of bad mouthing. But a lot of these type of comparisons are designed to be. The thing is that if the soviets stuff were so bad, WhyTF do americans ride the rockets of the modern day soviets to the ISS? The design philosophy of the russians remain the same as in the past. Over-design is probably for profit especially when the money is easy to print. In tougher times, you'd go ride the imprecise soviet rockets instead :)

the 8bit russian tune can be ken's theme song...

Titan missile computer 😳

8:09 My very old digital arm watch is about 5 second off per week.

If it is externally clocked I suspect any failure of the external reference would be grounds for an abort. I suspect the short amount of time between such a failure and reentry wouldn't be long enough for clock drift to become a problem.

@johndododoe1411

Жыл бұрын

You have to convert the time error to a position error at orbital speeds. At Mir/ISS speeds, an accumulated error of 100μs would miss the arrival by more than 2 feet.

Es electrónica del año 1970, deben colocar los computadoras del Soyuz actuales que son más miniaturazadas

Does it count for the fact that I am on a A380-300 half way between Madrid and Chicago?

@nmccw3245

4 жыл бұрын

FuquarProductions - yes, you are in a different space time reference frame.

11:50 in this context, what does "aging" mean?

@SeanBZA

4 жыл бұрын

Crystals, along with most mechanical parts, change charactaristics with tiume after you have done machining work or heating to them. thus the quartz crystal element will have a defined measured frequency right after it is cut, polished, had plates sputtered to it, mounted into a vibration damping frame, and placed into the vacuum sealed housing. As time goes by the crystal stress relaxes, and thus the frequency changes slightly. As well the stress changes as it is used, and also causes it to change. Thus you get an aging solely from when it was made, unpowered, and another added to it from powered operation. collectively they are all "aging", and the change decreases with time, till after some time ( generally 2 years) the change with time is very small, much less than the change due to temperature change or voltage it is driven at. Almost all more than ultra cheap quartz crystals thus are kept in storage for a year or so after the cutting and polishing, before they are finally packaged and trimmed to final frequency, so that the bulk of the aging has happened, and the small amount of extra stress in trimming (either by using a laser to remove material, or grinding some off) is reduced, so that the unit will meet a tighter initial spec, and also have reduced aging. Cheap crystals like for watches and low cost use are not so controlled, you will find some that are perfect right from the factory, and others will drift a few seconds a week, and never stop.

@yorgle

4 жыл бұрын

@@SeanBZAAh! Thank you for the detailed reply! That makes sense now. :D

The huge difference is that Sojoez only had to fly circles around earth, Apollo needed to reach the moon. Might this explain the clock is running less accurate?

@CuriousMarc

4 жыл бұрын

I would think so.

PCB reversing by GIMP? Why not! Yeah...)

I expected that you would have one of those cheap used rubidium oscillators of eBay

One thing that I noticed in part 3 is that you're running it on 24 volts even though the Soyuz works on 28 volts. I don't know if that would make any difference (I doubt it), but that's my 2 cents.

@CuriousMarc

4 жыл бұрын

Yes, nominal is 28V. But no, tried it, it doesn't make any difference. Actually the clock is pretty happy counting from a very wide range of voltages.

There are obviously some troubles with that clock. One of the chips disturbs the whole circuit during operation.

4 s/day for reference, could be achieved by a relatively run of the mill mechanical wrist watch of the day, if correctly calibrated and aligned. The COSC Swiss chronometer standard for mechanical time pieces calls for an average daily rate: −4/+6 and this is not particularly difficult to do if the watch is reasonably well engineered. The Soviet eta Sekonda USSR 2614.2H based mechanical watch from around 1972 that I am wearing for example meets this standard, purely because it has been recently serviced and adjusted. A typical modern cheap quartz watch for comparison is going to put in around 15 s/month, or 0.5 sec per day, so that quartz oscillator is not particularly good. Despite all of that gold plating and over engineering, I have to say I'm somewhat surprised that your space clock is not more accurate than that. en.wikipedia.org/wiki/COSC 17jewels.info/movements/p/poljot/poljot-2614-2h/

@CuriousMarc

4 жыл бұрын

Yes, there are exceptional mechanical time pieces that can do 4 seconds a day and are portable. And I do have a COSC certified chronometer. But it's far from being "easy" or "run of the mill". These are exceptional movements, and my wallet reminded me so when I bought it. And that's without the space vibe/shock/temp/acceleration/pressure requirements.

i made a led blink with a 486 lpt1... mom says i am read to leave the home at 45...

Will you try to simulate a flight from the titan computer??? 😀😀😀

@user2C47

4 жыл бұрын

Likely. This computer is not for terminal guidance. It will be interesting to see what it does after the payload decouples.

Do the same with an american clock. It will be 0.0001% more accurate, but ninety billion times more complicated as a device.