wow, that must have supercool to be a part of!

Well here is a dumb question ... when you saw Star Trek The Motion Picture was Voyager's (Voyager 6) appearance a surprise or were your bunch in the know beforehand?

Must be really cool to be part of something that will likely be the only remaining artefact of humanity in the very distant future.

I'm envious. Awesome!

Wow! Do you know if FORTRAN was used for the CCS or was it all assembly?

It would take 30,000 years to get there... so most of us won't sit around and watch it. : )

Tape drive, not hard drive.

That was a huge amount of RAM for that time period. At that time, 1KB of SRAM was over $100. The real clock was likely 10-20 times the frequency you're thinking. The 11 kHz is instruction cycle time, many clock ticks to make that happen.

​@@mikebrown7366 it looks like a supercomputer for the '70s.

That scale is what? 10^-5 watts received at the DSN? That's like hearing somebody whisper in a tornado and still being able to tell what they're saying. I'm surprised the tape drive is still working after all these years.

Thank you for your work

@@BlackEpyon it's around 10^-19 W.

IC’s were developed first for ICBM’s, which I guess are nominally space craft.

When Gerard O'Neil asked his class to estimate the ROI on the Apollo program to everyone's surprise (including his) the found that *just* the taxes on *just* the improvements on *just* the telecom industry would have paid for Apollo by the mid-'80s.

www.goonhilly.org/antennas/ghy-1-arthur You should check this out another amazing work

I remember that it has 16 kilobytes of memory

This one is about Apollo Guidance Computer. Not Voyager, but still - a very interesting sneak peek into the hardware of the era ukposts.info/have/v-deo/anuElZ54poV9xYk.html

If you can't find documents NASA or others have put online, you can also often research those documents yourself through NASA's Technology Transfer Program. For access to Apollo- and Voyager- era detailed documents, you'll need to be a US citizen and resident. They do put a lot of software and information out there for worldwide distribution, but when I researched Apollo documents in March 2017 through the program, US residency was required. They update their catalog every two years, so the links below are a bit stale relating to the third release covering 2017-2018 made in early 2017. I imagine there was a fourth dump made in early 2019. ___________________________________________________________________________ SOURCES [1] NASA Technology Transfer Program channel on UKposts, “Download NASA Software for Free!”, 3/1/2017: ukposts.info/have/v-deo/gnmhrZlveJx-u40.html [2] NASA Technology Transfer Program website (start here for application and download): software.nasa.gov [3] NASA Technology Transfer Program, “NASA Software 2017-2018 Catalog”(PDF): technology.nasa.gov/NASA_Software_Catalog_2017-18.pdf [4] NASA Technology Transfer Program, “NASA Software 2015-2016 Catalog”(PDF): software.nasa.gov/NASA_Software_Catalog_2015-16.pdf [5] My writeup of the program on the @ScienceVsUniverse group on Facebook: facebook.com/groups/sciencevsuniverse/permalink/939080342894377/

said information may be available. KLabs has the schematic pack for the Apollo Block II guidance computer (accessible from the UK as of March 2021). Voyager used the same basic computer design as the Viking Mars probes, so you might have luck finding schematics through a search for that. JPL has, in its paper archive, about 15 cubic feet of pretty much every document ever printed concerning the Voyager program pre-launch. A lot of that may still be compartmented under 22 USC chapter 39 due to the fact that launcher hardware is still largely based on military hardware development.

None. www.geek.com/news/nasa-seeks-programmer-fluent-in-60-year-old-languages-to-work-on-voyager-1638276/

Yeah, he didn't get into the camera mount workarounds they had to use because the tracking platform for the camera on Voyager 2 jammed after visiting Saturn, so they had to rotate the entire spacecraft to keep the camera pointed in the right direction for the multiple-minute exposure times en.wikipedia.org/wiki/Voyager_2#Encounter_with_Saturn though they eventually got the camera platform working again. He could easily do another whole talk on the various work-arounds and remote fixes they've done to keep the spacecraft running.

Always has been

Yeh definitely impressive! Not the case at all for spacecraft nowadays though - systems are just as redundant as they've always been, depending on the mission requirements of course

I don't know why you're antagonizing domestic and space technologies. They have different design goals. If that thing was designed to not act up, or the system was designed to be resilient, its cost would be 10-fold if not 100-fold. You would simply not buy it.

Actually, there's just the same attention to detail today in military, aviation and space systems today; hardening and redundancy of various types depdending on the engineering constraints which is what Aaron Cummings is focusing on. I've been working a lot with FPGAs, which can be thought of as the 'next level' beyond GPUs for high-performance computing. When you're planning to code an algorithm into FPGA hardware that is designed to run for perhaps weeks or months at a time, if not years, you have to take things into account like cosmic rays coming along and performing random bit flips in any register or memory location. So redundancy and recovering from errors is key to detecting such issues, complicating the design but making the results far more reliable reliable and statistically predictable. I also started working with digital electronics and computers professionally beginning in 1977, first in NYC as a high school teen and then at MIT working for Dr. George Ricker who's the chief scientist on NASA's TESS mission which just wound up (and replaced the Kepler mission most folks have heard about). Coincidentally, that was the year the Voyager 1 and 2 missions were launched. At MIT when I worked for Dr. Ricker, circa 1980-1981, we were making the same transition from mid-1970s computers based on TTL processing boards and core memory (we had 32Kx16-bits in our Data General Nova 2 hand-me-down from another, better funded, lab). From the presentation, the Nova 2 looks very similar to the RCS and AACS computers except for the 4-bit nibbling of the fetch/store to memory; the Nova 2 would fetch/store 16-bits at a time bit with 4x the amount of electronics. But the Nova 2 was insufficient for the huge 128x128 images [ !! ] we were getting from the first Texas Instruments CCD devices we were mounting on telescopes for astronomical measurements in the visible light and X-ray spectrums. So we hand-built a custom 256Kx16-bit frame buffer using S-100 boards with CMOS memories on them, and for a while we gained some bragging rights for having the most memory in any single system across all of the labs in MIT's Center for Space Research (which I should mention is where the Apollo-era computers were designed and built a decade earlier). That frame buffer, though it lacked a CPU and was controlled by the Nova 2 as an IO device, was roughly comparable to the FDS imaging computer on Voyager, which may have had up to perhaps 512Kx18 of CMOS memory to hold a single 640x640 image, perhaps more (though that would make for more power requirements and circuitry). It's true this is nothing compared to what is possible today; TESS has gigabytes of memory on board (I think perhaps 10GB), but then having such tight memory constraints leads to good memory-efficient coding practices, error recovery, and fault-tolerant designs.

See: en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#Life_span

@@gordonrichardson2972 That makes sense, the radiation from the plutonium would tend to p-type dope silicon by knocking holes in the crystal lattice. It would probably degrade faster than a thermocouple. Maybe the concept would work better with a wide bandgap semiconductor, not available in the 1970s.

We did. And have, still, probes around Jupiter/Saturn, etc right now... Crack open yer Googler...

I was wondering myself if New Horizons has the potential to overtake Voyager in terms of distance from the sun, but it turns out that NH is travelling slower than either Voyager and that the difference in speed is widening. So any chance at catching either V'ger in terms of distance from the sun would be with some new mission yet to be launched.

General Electric 18-bit TTL CPU.

NASA has released a trove of mission documents related to Apollo and later missions, so there's likely to be quite a bit of stuff available through NASA, especially through their Technology Transfer Program if you're a US citizen and resident (they have a more limited set of documents and software available worldwide). I was able to receive all sorts of amazing Apollo-era PDFs for the design of various subsystems back in March 2017. You might have similar luck regarding Voyager designs if you're willing to apply to the program and do a bit of digging through their massive catalog. The links below are a bit stale, corresponding to the third release of the catalog for 2017-2018. They release the catalog every two years, so there should be a corresponding fourth dump for 2019-2020. _________________________________________________________________________ SOURCES [1] NASA Technology Transfer Program channel on UKposts, “Download NASA Software for Free!”, 3/1/2017: ukposts.info/have/v-deo/gnmhrZlveJx-u40.html [2] NASA Technology Transfer Program website (start here for application and download): software.nasa.gov [3] NASA Technology Transfer Program, “NASA Software 2017-2018 Catalog”(PDF): technology.nasa.gov/NASA_Software_Catalog_2017-18.pdf [4] NASA Technology Transfer Program, “NASA Software 2015-2016 Catalog”(PDF): software.nasa.gov/NASA_Software_Catalog_2015-16.pdf [5] My writeup of the program on the @ScienceVsUniverse group on Facebook: facebook.com/groups/sciencevsuniverse/permalink/939080342894377/

The data format is the same as was used on the Apollo flight control computers. I am guessing a strong relationship.

you can check here: nssdc.gsfc.nasa.gov/nmc/spacecraft/displayDataset.action?spacecraftId=1977-084A

This is about capturing and returning, but similar problems should arise: what-if.xkcd.com/38/ The relay craft would need to be fast enough to close to a reasonable distance in a reasonable time and then slow down again, so that you dont overtake Voyager, as that wouldn't do you any good . . . And it would need sufficient communications gear and power supply. I have a hard time seeing a 34m oder 70m dish mounted on a spacecraft (that's the size of what the Deep Space Network uses). And then the question is for how much longer you' get usefull data from the Voyagers, even if you manage to pull all that off. My guess would be that a purpose built interstelar exploration spacecraft would be more usefull. You could use the results from Voyager to select relevant instuments (i.e. a camera probably wouldn't be of all that much use) and (maybe?) put it on a faster trajectory, as you wouldn't need to visit any planets, except for gravity assists.

I wonder if a moving parts inside an engine would knock the satellite off course ?

Basic radio data communications - if you have a big enough dish pointing in the right direction you can receive data. Doubling the distance reduces the power received by a factor of four. The transmitter power is slowly declining but the receiver sensitivities have improved by several orders of magnitude since the probe was launched (and we can replace the receivers).

The Deep Space Network (DSN) ground stations have been continuously upgraded over the decades with larger and more powerful components. The communication failure will ultimately be the downlink from Voyager (whisper), not the uplink from the DSN (shouting).