>> 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.
> 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.
Wrt. 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.
Ceramic side-brazed DIPs look very futuristic to me for some reason, especially when the carrying substrate is light colored. Plastic packaging is pretty dull in comparison.
While 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.
I’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.
This 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.
You 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... :)
One 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.
When 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.
-That's very true, I should have been more specific - I mostly did circuits with the occasional IC in it - trying to dead bug a QFN or TSOP gets old fast. :)
The 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?
It'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.
Surprisingly 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!).
If 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.
I 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.
A 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.
I 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.
I 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...
I 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
>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.
I 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.
Okay 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.
Wow, 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.
If 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...
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...)
I assume in the context, he means "GPS" to mean radio based position and velocity fixing, since it's opposed to dead reckoning.
You're talking about NAVSTAR GPS, which is what most people refer to as simply "GPS". However other radio based US military nav sats date back to the 50s with the Navy's TRANSIT system, and Timation 1 was launched in '67, which was probably the first sat with a signal helpful for real-time, fast moving calculations, but was almost certainly too big to fit in a space ship at the time. Usable LORAN dates back to ~1940, if you don't limit it to sat based systems.
I'm not familiar with what the Soviets were capable of at the time in terms of either their independent nav systems, or ability to take advantage of the US ones, but it's reasonable to think they were putting as much military effort into it as the US was. Hell, a lot of info on the US history has only been ~recently declassified.
Point being, the space race happened specifically to develop this type of nuke delivery technology. At the time, this thinking definitely included manned space capsules (think nuclear bombers, but flying in space), as well as ICBMs, both of which would require precise navigation.
That said, the IMP merely calculated and displayed updated position based on manually input orbit parameters, which were calculated on the ground and radioed up.
Those, in turn, were based on location/velocity observations using both radio and radar range-finding, but all ground-based.
> 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.
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.
The 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.
> 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.
I recall as a kid seeing in electronics magazines in the late 70s some ads about a clock kit everyone could solder in a evening thanks to a then new module called MA1001. Some searches confirmed it was introduced in the mid 70s.
It 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_.
Thanks 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?
The 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.
CuriousMarc [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.
Interestingly, Shenzhou isn't a Soyuz derivative -- it's significantly larger and has other divergent features (its orbital module can allegedly stay docked to another vehicle even after the crew capsule detatches for re-entry).
As I understand it, China is excluded from treaties governing cooperation in crewed spaceflight that go back to the Apollo-Soyuz link-up and include other third parties such as ESA and Japan: this locked them out of the ISS program. So they had to develop their own space station, too.
Even 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.
Less 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.
This 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.
It'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.
Assuming 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.
I'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.
A practical difference between TTL and CMOS is that a CMOS gate draws negligible current when it's sitting in one state (1 or 0). It only draws current when changing states. So CMOS circuits can run at much lower power, and this power consumption decreases as the gates get smaller. This in turn means you cram more gates onto a slab of silicon before heat dissipation starts to kill you. And it's kind of an invitation to miniaturize in the pursuit of both higher computing power and higher speed... nice.
Now I'm dating myself, but there was a time period when CMOS gates were slower than TTL or even faster logic families like RTL. So a fast machine like the Cray was built with RTL, if I recall correctly. But eventually CMOS won this race.
The Cray-1 used bipolar ECL (emitter-coupled logic), which was very fast but power hungry. Thus, the Cray-1 needed to be immersed in Freon for cooling. You can think of ECL as differential amplifiers that steer current down one path or another.
RTL (resistor-transistor logic) is entirely different. It was used in the Apollo Guidance Computer because that's all integrated circuits gave you at the time, but it's not very good. (The inputs affect each other because they are only separated by resistors. Even diode-transistor logic is much better.)
ECL is fast but hot because the transistors are never fully saturated, so current is always flowing.
CMOS is more like the electronic equivalent of a stiff mechanical lever system. Logic voltages change the charge distribution inside the MOS transistors. There's almost no current flow outside of them.
This is great for super-low power draw, but it's not particularly snappy, it can't drive LEDs directly, and it's not happy driving long wires without buffering. It's also very easily damaged by static electricity - which is why wrist grounding straps are a thing. Because the transistors are so tiny it's easy to scale it to VLSI.
TTL is mid-way between the two. The transistors saturate cleanly, so switching is faster than CMOS. The source/sink currents are much smaller than with ECL, so power requirements are manageable, although switching glitches need good decoupling. It's a robust and reliable system, with low-power options. But it's not as dense as CMOS, which is why 74xx series TTL never got any more complex than a simple 4-bit ALU, while MOS soon expanded into full 8-bit VLSI microprocessors.
Fast enough for practically all processors made today
> it can't drive LEDs directly
That depends on the design, but CMOS chips generally have much better symmetric output characteristics than TTL ever had. Most MCUs can drive quite some current on the output pins, and 74HC and similar logic families can certainly drive LEDs.
> 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.
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.