10 ms·
Inside the digital clock from a Soyuz spacecraft
- ericwood 7y agoWhile American resistors are usually labeled with colored bands, the Russian resistors are green cylinders with their values printed on them One nice thing about Russian ICs is that the part numbers are assigned according to a rational system, unlike the essentially random numbering of American integrated circuits. This makes so much sense, it's a shame this style of labeling didn't catch on. It would have made my EE labs in college so much easier.
- jgrahamc 7y agoI agree on the resistors. The resistor colour code coupled with poor quality of colours on the actual resistors has me frequently reaching for a multimeter to just measure the resistance.
- blt 7y agoI just end up not reusing resistors. I have the unused ones in labeled drawers. Once I lose track of a resistor's value, I add it to the pile of components that need sorting. I actually sorted that pile once for fasteners, but resistors are so cheap...
- other_herbert 7y agoI remember going to a small electronic supplier for custom and mainly military things around 1999... The assembly folks would not waste time on getting a resistor and several other parts of they fell and at the end of the day the sweepings would be sold in a miscellaneous bag of parts
- daveslash 7y agoThe descriptions of the American components (resistors, diodes, etc...) reflect what I've seen in all of the consumer electronic components that I've busted-open here in the U.S. -- ones which are often made outside of the U.S. The fact that these consumer electronics are built according to the American way as opposed to the Russian way - is that a reflection of selling to a U.S. market, U.S. companies selectively working with manufacturers that do things in a familiar way, general wide-adoption of the U.S. ways, or something else? If I were to be in Russia or a former Soviet state, would I see consumer electronics looking more like this Soyuz clock?
- dfox 7y agoSurprisingly large amount of soviet era consumer electronics are built quite similarly and use what in essence are military/space grade parts (and meticulously made cable looms). I assume that this is simply caused by using whatever was available in large enough quantity in combination with slightly different engineering culture (cable looms!).
- dfox 7y agoIf I think about it I probably can pinpoint the reason for the soldered cable looms: not only in SSSR but across the whole eastern block in general there simply weren't any reasonably cheap and reliable board to board or board to cable connectors for general use with reasonable density. Edit to add: there were various ribbon cables used in eastern block electronics, but mostly with hand soldered connectors, not IDC. Two exceptions I can think of are Shugart-compatible floppy drives (although some Czech computers actually use ribbon cables with hand soldered board-to-card connectors) and some Metra-branded measurement equipment which uses MicroD-like IDCs internally.
- blattimwind 7y agoIt's a reflection of color coding (with painted rings or dots) being vastly cheaper than printing text proper. Many lower cost European transistors (almost exclusively the TO-92 variety) were marked with colored dots or half-rings. Similarly some film and tantalum capacitors were marked with colored dots as well. Precision or otherwise higher grade (e.g. ceramic wirewounds) components were always usually marked with text.
- ani-ani 7y agoThis led me to this declassified document according to which Soviets used a mix of color codes and directly stamping values on resistor housings: https://www.cia.gov/library/readingroom/docs/CIA-RDP80-00809A000700030074-5.pdf https://www.cia.gov/library/readingroom/docs/CIA-RDP80-00809... The document is from 1950 though, so it greatly predates the standards used the 1983 Soyuz here.
- gen3 7y agoI’m color blind. The markings would make everything so much easier. Having to check with someone else to make sure I get my colors right is such a pain. I hope I can order some. Edit: If anyone can find labeled resistors for a reasonable price, I would be grateful.
- lb1lf 7y agoThis is why I loved it when introduced to SMT devices. Rather than those pesky colour bands, values were stamped on in a rational manner - two digits value, one digit power of ten. Say, 106 for a 1MOhm resistor, 102 for a 100Ohm one. My lab productivity soared.
- gen3 7y agoI found some of them. They look super helpful. How do you breadboard things with them?
- lb1lf 7y agoYou mostly don't - I had a decent setup for etching, so I just quick-and-dirtied a layout, put down a few extra pads where I suspected I might need some, processed a board and gave it a go. The one important thing is to not pinch on the pincers - buy a good pair... :)
- gen3 7y agoOne last question: Where do you order them from? The labeled kits I see are around $120 and I’m on a college student budget. Thanks for answering my questions.
- lb1lf 7y agoWhen I was on a student budget, I mostly asked my lab tutor kindly if I could help myself to the parts stocked by my university - the lab people were so happy someone actually wanted to build something that I was basically given free access to the parts bins. Additionally, regional distributor ELFA had bins of 1000 1% 0805 resistors for ~$10/ea, so I just purchased a couple of bins at a time as I needed them until I had an E12-ish set. If there is one nearby, I'd strongly suggest you visit a maker space - chances are they have SMT kits already.
- blackrock 7y agoWhat’s an example of the Russian nomenclature vs. the American style?
- kens 7y agoA typical Soviet IC part is 134ЛБ2. The 134 indicates the TTL family. The Л (L) indicates it's a logic gate IC and ЛБ indicates it's a NAND/NOR. If you know the categories, you know what more or less what the IC does. A typical US IC part is 7490. 74 indicates the TTL family. But the 90 is arbitrary. The 7490 is a counter but 7491 is a shift register. The part number doesn't give you any idea what the IC does. See Wikipedia for details on the Soviet IC system: https://en.wikipedia.org/wiki/Soviet_integrated_circuit_designation https://en.wikipedia.org/wiki/Soviet_integrated_circuit_desi...
- bborud 7y agoI suppose the color coding was a cost issue - that is: I'm assuming the technology to reliably and legibly print small numbers on somewhat irregularly shaped cylindrical objects was more expensive than applying color bands back when this became a common way to do it. I dislike color bands for two reasons: 1) I can never remember which color is which digit (it follows the rainbow, but not quite). 2) The colors can be hard to identify due to varying color shades, and quality ("is that read or brown?"). It also doesn't work well for people who are color blind.
- cstross 7y ago> Due to the end of the Space Shuttle program, Soyuz is now the only spacecraft capable of carrying a crew into orbit So I'm guessing the Shenzhou program doesn't count? https://en.wikipedia.org/wiki/Shenzhou_(spacecraft) https://en.wikipedia.org/wiki/Shenzhou_(spacecraft) (Yes, I know the OP goes on to say "and used for flights to the ISS". Still irritatingly inaccurate.)
- kens 7y agoThanks for the comment; I've removed the offending sentence. (edit: cstross is right and doesn't deserve downvotes.) Wikipedia says "Soyuz has served as the only means for crewed space flights in the world since the retirement of the US Space Shuttle in 2011", so I guess that's wrong? https://en.wikipedia.org/wiki/Soyuz_(spacecraft) https://en.wikipedia.org/wiki/Soyuz_(spacecraft)
- daveslash 7y agoThanks Op. How did you come into possession of this clock? Edit: And does it still work?
- kens 7y agoCuriousMarc [1] bought the clock at a space auction. We hope the clock still works. We plan to power it up and get it working, but first I needed to reverse-engineer the circuitry to figure out how to power it. [1] https://youtube.com/curiousmarc https://youtube.com/curiousmarc
- egdod 7y agoThat’s wild. How much did it cost?
- mschuster91 7y agoThe Chinese program is China only, unavailable to the rest of the world - Russia in contrast sells to everyone, meaning that "the world" only has Russia as provider.
- blattimwind 7y ago> These are mostly 14-pin "flat pack" integrated circuits in metal packages, unlike contemporary American integrated circuits which were usually packaged in black epoxy. There are also some 16-pin integrated circuits, encased in pink plastic. It's worth pointing out that flatpacks (both ceramic and EP) were and probably still are a mainstay of military and aero electronics. These were never used in consumer electronics. Apart from microprocessors and EEPROMs, consumer electronics never really used ceramic or hermetic metal packages for cost reasons. Perhaps the most common components would be TO-3 power transistors and small metal can transistors before TO-92 and similar packages obsoleted all of those. > Many of the components in the power supply look different from American components. While American resistors are usually labeled with colored bands, the Russian resistors are green cylinders with their values printed on them. High grade or high precision resistors usually had their value printed on them, though. Meanwhile, only larger SMD resistors have markings today (I think they stop applying them below 0604 imperial). > The Russian diodes have orange rectangular packages (below), unlike the usual cylindrical American diodes. Semiconductor packages were all over the place in the past; I've seen cube-ish moulded diodes, resistors and capacitors in European stuff. Overall this thing looks a lot like something from the mid 60s, not so much mid 80s. In that case, American stuff from the same period looks pretty similar, quite possibly due to copious copying by the Russians. > One nice thing about Russian ICs is that the part numbers are assigned according to a rational system, unlike the essentially random numbering of American integrated circuits. On a related note, I really like IEC/ISO schematics for this reason, because we have a graphical language to describe logic and this means logic devices appear as a composition of symbols which explain the function of the gate to anyone who knows this language. On American schematics only the most basic gates (AND, OR, NOT, ...) have symbols, everything more complicated than that is generally drawn as a box with the part number ('193) in it and the pins just labelled with their abbreviations.
- dfox 7y agoWrt. to flatpaks it is somewhat interesting to note, that very often when there is some kind of ASIC (think alarm clock or calculator or even “PDP-11 on a chip”) in 80's soviet consumer electronics it is packaged in metal/ceramic hermetic flatpack with legs bent and THT soldered.
- ohadron 7y agoIt's amazing to think that this device was produced several years after the class simple casio watch we all know. Same functionality more or less, probably a fraction of the weight and cost. I'd attribute the difference to how military/government projects pan out and not necessarily to the less advanced soviet IC abilities. There are many similar examples in western military equipment.
- dfox 7y agoAssuming this thing was designed in early 80's (which it probably was given the LQ470-like DIL 7segment LED displays) there certainly was soviet made NMOS ASIC that implemented most of the functionality in single package. But similarly to contemporary western counterparts it required bunch of funky supply voltages (albeit the supply rails used by soviet alarm clock ASICs are nowhere near the supply funkiness of Sanyo's essentially AC powered alarm clock ASICs) and were nowhere reliable enough to be used in space.
- blattimwind 7y agoThe LED display could have been an upgrade on an older design. I assume Soyuz always had a clock.
- Luc 7y agoThe conclusion seems a bit strange. Why does the Soyuz clock contain over 100 chips instead of being implemented with a single clock chip? Soviet integrated circuit technology was about 8 years behind American technology, so TTL chips were a reasonable choice at the time. Because in the paragraph above: I expected the Shuttle computer to use 1980s microprocessors and be a generation ahead of the Soyuz clock, but instead the two systems both use TTL technology, and in many cases almost identical chips.
- m0zg 7y agoIt was way behind yes (and much of it was ripped off, China-style, from Western designs), but I agree it's weird to compare a _computer_ with a _clock_.
- kens 7y agoThe point is that the Shuttle's TTL chips were more advanced as far as performance, using Fairchild's FAST line. The Shuttle also used many TTL chips that were more complex. This is consistent with the CIA's claim that American ICs were 8 to 9 years ahead. But it's interesting that the Shuttle was still using TTL, and many of the chips were very basic, like the quad NAND gate chip. So the difference between the two boards was surprisingly incremental, rather than a jump to MOS chips or microprocessors.
- metaphor 7y ago> The point is that the Shuttle's TTL chips were more advanced as far as performance, using Fairchild's FAST line. This. The author points out the 54F00, seemingly distracted by the 54'00 part and similarities in TTL glue logic layout that the F part is completely dismissed without acknowledging that these chips had sub-4ns edge rates and were indeed fast while remaining compatible with older TTL families. Throw in high SMD density on a multi-layer controlled-impedance PCB designed to survive brutal operating environments when PCs and CAD were still in their infancy...even today, it's humbling to contemplate just how much work would have been required to qualify such a design. > But it's interesting that the Shuttle was still using TTL... These systems had super long lifecycles and were required to be extremely reliable. I'd be surprised if the contractor that was responsible for the design would have been allowed to integrate any IC that wasn't listed in a QML.
- flipflipper 7y ago>However, the power supply uses a more complicated design to provide electrical isolation between the spacecraft and the clock. I'm not sure, though, why isolation was necessary. I believe this is to maintain a single point ground, usually the chassis on a spacecraft. The chassis of the clock is probably connected to the isolated side's ground, which avoids ground loops when the clock is integrated into the S/C. More detail on grounding and isolation in S/C is covered here: https://standards.nasa.gov/standard/nasa/nasa-hdbk-4001 https://standards.nasa.gov/standard/nasa/nasa-hdbk-4001
- analog31 7y agoI wonder if there would be a fair amount of current flowing through the "ground" of the craft as it went through the ionosphere and then into whatever ion flux the sun is spitting out. They might have to be really careful about treating the whole chassis as a circuit.
- blakes 7y agoHere is the video where they open up this very clock for the first time: https://www.youtube.com/watch?v=JBIhzEZkWEA https://www.youtube.com/watch?v=JBIhzEZkWEA
- Waterluvian 7y agoOkay that physical globe as an item on the Soyuz dashboard is amazing. I need to know more about that. I imagine it's gimballed and a computer moves it to the GPS or dead reckoned position as the Soyuz orbits over the Earth. What a really cool output device.
- kens 7y agoThat's the Globus IMP and dates back to 1964. Wikipedia has details: https://en.wikipedia.org/wiki/Voskhod_Spacecraft_%22Globus%22_IMP_navigation_instrument https://en.wikipedia.org/wiki/Voskhod_Spacecraft_%22Globus%2...
- eigenvalue 7y agoWow, what an amazing device! I’m surprised this isn’t better known in the West. I’d love to understand better how it actually worked in a detailed way. Mechanical computers are so cool.
- kens 7y agoIf anyone has a Globus indicator sitting around, I'd be happy to open it up and reverse engineer it :-)
- bigiain 7y agoThat would be _so_ cool! BTW, do you have any measurements of that clock you could share? I'm seriously considering mocking one up just for the cool factor... It'd be nice to get it at least approximately the right size. (I'm also considering building a working model Globus indicator too. Maybe I'll just size everything based on the most suitable globe I can find...)
- bigiain 7y agoIf you're ever anywhere near The Bay Area, go do the tour of the Nike Base in the Marin Headlands. They've got a _super_ cool mechanical targeting computer there... https://www.nps.gov/goga/nike-missile-site.htm https://www.nps.gov/goga/nike-missile-site.htm
- m0zg 7y agoEven back then, the Soviet space program had the electronics to make this much less complicated. Remember, in 1986 they had the Buran shuttle which flew to the orbit and landed fully autonomously, under computer control. The clock was probably developed much earlier, and then perhaps slightly modernized with LEDs and such. Developing a new clock for spacecraft would probably take a year or two, for all the testing and certifications, so nobody bothered.
- geocrasher 7y agoThis was my thinking as well. Spacecraft are already incredibly complex. Building a new clock for the sake of building a new clock surely wasn't a priority.
- orbital-decay 7y agoLess complicated isn't always good. There was no problem driving the clock display with the onboard Argon-16 of course, but the clock was decoupled into a separate device to not have a single point of failure, and also to replace the old onboard chronometer which was even more complex and failure-prone.
- m0zg 7y agoThat's not what I meant. I meant using more specialized ICs or a separate microprocessor. It's not like cost was much of a concern there.
- rdtsc 7y ago> Russian resistors are green cylinders with their values printed on them. The Russian diodes have orange rectangular packages (below), unlike the usual cylindrical American diodes They have color coded Russian resistors, probably just for smaller sizes. Diodes have a variety of shapes, but I don't remember seeing rectangular packages like that one either. Some of those component might have also been specially sourced high tolerance components that might be different than what you'd find in consumer electronics? > The logos on the integrated circuits reveal that they were manufactured by a variety of companies. Oh very interesting. I have been wondering about what those logos meant when I used to play with electronics back in the day. They even have a link to the full list http://madelectronics.ru/book/prominfo/2009-04-16-08-29-39-318.htm http://madelectronics.ru/book/prominfo/2009-04-16-08-29-39-3....
- ben7799 7y agoThis article is great... much thanks to the author. This kind of stuff is fascinating.
- gautamcgoel 7y agoGreat piece of history. Can someone explain the difference between TTL and CMOS chips?
- kens 7y agoI'm not sure how much explanation you want. The short answer is that TTL (transistor-transistor logic) is an older logic family, while CMOS (complementary metal oxide semiconductor) is what's used nowadays, such as in microprocessors. In more detail, first there were bipolar transistors (NPN and PNP) and later MOS transistor (NMOS and PMOS). Bipolar transistors are your basic semiconductor transistors with three layers of semiconductor. MOS (metal oxide semiconductor) transistors have an insulating oxide layer between the silicon and the metal (or polysilicon) on top. MOS transistors were developed later than bipolar, and started to become popular in the 1970s. One type of logic that you can make from bipolar transistors is TTL (transistor-transistor logic). TTL is better than earlier logic families such as resistor-transistor logic (RTL) or diode-transistor logic (DTL). TTL was cheap, reliable, fast, easy to use, and popular with minicomputer manufacturers. TTL has two main problems, though. It uses a fair bit of power, and you can't make it very dense. I.e. you can't put a lot on a chip. MOS, on the other hand, has the advantage that you can make very dense circuits from it. (I.e. Moore's law applies.) NMOS was used for early microprocessors such as the Z-80 and 6502. The problem with NMOS is that it uses resistors (sort of) in the logic gates, and these waste power. The solution was CMOS, complementary MOS. You use both NMOS and PMOS transistors (the complementary part), and you can get rid of the resistors, and your chip uses very low power. The problem with CMOS is it's more complicated because you need two types of transistors, and twice as many (sort of). However, the need for low power won out in the mid-1980s and microprocessors such as the 80386 started using CMOS. Use of CMOS has continued to the present. I'm oversimplifying the history somewhat. The books "To the digital age" and "History of semiconductor engineering" go into much more detail.
- gautamcgoel 7y agoThis was great context, thanks for the explanation!
- analog31 7y ago
- kens 7y agoI just noticed that HN has the mobile link to my article, so the images are fairly small. You can click on an image to see a larger version, or go to the regular site: http://www.righto.com/2020/01/inside-digital-clock-from-soyuz.html http://www.righto.com/2020/01/inside-digital-clock-from-soyu...
- sandworm101 7y ago>> However, the power supply uses a more complicated design to provide electrical isolation between the spacecraft and the clock. I'm not sure, though, why isolation was necessary. Because soviet spacecraft, as with all spacecraft at that time, were designed to survive all sorts of failures. The clock is an absolutely essential part of the spacecraft. It needs to keep running even when everything else is failing, especially when everything else is failing. A space clock needs to be both integrated into a dozen other systems, and able to cut itself from those systems when necessary. Cosmonauts in a failing capsule, waiting to fire the return burn necessary to get home, won't be looking out the window. They will be looking at that clock.
- WalterBright 7y agoI designed and built a digital clock around 1976. It has around 40 ICs in it. It never worked right :-)
- 0xff00ffee 7y ago> While American resistors are usually labeled with colored bands, the Soviet resistors are green cylinders with their values printed on them. Smart! The color band system has +ve and -ve, but overall I hate it. But better than caps with their 104 = 100,000 pf/nF? I've known the US color band system since I was a kid, but damn the base color of the resistor epoxy has a huge impact, as does the low wattage high precision: you need a magnifier to read all 5 bands on a 4mm resistor.