Antique Voyager Technology 293
sea_stuart writes with a story from the Tidbinbilla space tracking station, outside Canberra, Australia. It is still communicating with the two Voyager spacecraft 30 years after they were launched and 18 years after Voyager 2 passed close by Neptune. Here's a little background on Voyager 1 and Voyager 2. "The bank of computers that would look at home in black-and-white episodes of Doctor Who cannot be junked... [T]he 1970s hardware is now our world's only means of chatting with two robot pioneers exploring the solar system's outer limits. Today Voyager 1 is humanity's most remote object, 15.5 billion kilometers from the sun. Voyager 2 is 12.5 billion kilometers from it. Both continue beaming home reports, but now they are space-age antiques. 'The Voyager technology is so outmoded,' said Tidbinbilla's spokesman, Glen Nagle, 'we have had to maintain heritage equipment to talk to them.'"
It's Alright... (Score:4, Interesting)
I'm sorry... I'm bitter...
32 bits a second (Score:4, Interesting)
(32 bits) x (60 seconds) x (60 minutes) x (24 hours) x (365 days) x (30 years) = (30,274,560,000 bits)
(30,274,560,000 bits) / (8 bits) / (1024 bytes) / (1024 KiB) / (1024 MiB) = (about 3.5 GiB over 30 years)
I don't think a modern computer would help, because it's clear that Comcast is seriously throttling their torrent connection.
Re:Functional replacement with modern components? (Score:4, Interesting)
Not really. As long as you have people who understand the hardware and a supply of old machines for spare parts you should be able to keep things ticking along for decades.
In my last job we ran the entire Melbourne traffic signal system off PDP 11/84's and 83's. Its a good way to keep your wire wrap skills up to scratch.
Re:I've got an old dell they can use... (Score:3, Interesting)
Not that TFA can be trusted (honestly how would something be "too slow" for a computer? Does my processor get impatient?) but it kinda implies that these guy's primary responsibility is this computer. For the price of two senior engineers it really seems like they could cook up a modern replacement.
Seems odd that they don't just salvage the analog components and connect it to a modern computer... I guess I'd understand not touching it if it's deemed fragile...
Anyone know if the Voyagers rely on a heartbeat or something? If it's just a receiver I can't see why building a modern backup isn't worthwhile.
Re:I've got an old dell they can use... (Score:4, Interesting)
In order for something to be acceptable to NASA for use in the space program it has to be very thoroughly tested. This means you could write a software emulator that did everything required, but then it would have to run flawlessly for 10 years in order to be approved for use. You have to remember that these computers can also send commands to the satellites, so if they crash and send an erroneous command out, then that command will be actioned by the satellite.
I know this is highly unlikely, but it is not impossible so why risk it when the result of that one command could be that we lose both satellites for ever.
There is a mantra when it comes to dealing with any computer system that is running a mission critical app:
"If it ain't broke, don't fix it."
I would suggest that anyone wanting to be sysadmin, learn this. There are times when it doesn't apply but that is usually when the benefit of change out way the risks. In this case what is the benefit of upgrading the system at our end?
Relivs of a time... (Score:3, Interesting)
Re:I've got an old dell they can use... (Score:3, Interesting)
I'm sure you understand why... I think the conversation would go something like this:
IT: "This new system will cost $1bn, and will save $3bn/year in maintenance on the old system".
Management: "The previous system was supposed to cost $1bn to develop, and ended up costing $10bn. If I sign off on this it will be my ass on the line when the budget blows out, so I'll stick with known quantities thanks."
Awesome (Score:5, Interesting)
I am very glad that there are still people who monitor and maintain the Voyagers. They deserve it.
I worked on this project (Score:5, Interesting)
Re:it's cheaper, this way. (Score:4, Interesting)
A typical mainframe of 30 years ago would have done a lot of batch processing. But it still multi tasked. Only an embedded system would have had deterministic timing. And that is true of today as well.
I funded a hitch hiking holiday in Tasmania in 1986 by doing small withdrawals in the middle of the night when ATM's couldn't connect to the banking systems because overnight jobs were running.
Re:The reason for all that legacy equipment... (Score:4, Interesting)
Or more likely:
"Hello sir, my name is Tom, calling from your Houston of your Texas. With the client we are noticing a problem. Please to do the needful."
Re:I've got an old dell they can use... (Score:4, Interesting)
This kind of stuff is done daily in ham radio. I build a interface to read the old abandoned weather satellites slow scan TV signal with a soundcard and a connector plug. wrote the app in C in 2 hours and had a picture on screen the next pass.
I would have been faster if I though to record the last pass's audio and replay it for debugging, but no It took me 30 minutes to find a different bird passing over that I could receive.
Re:I've got an old dell they can use... (Score:2, Interesting)
1) It's not a software receiver, it's hardware
2) There IS a newer receiver, the Block V, that uses a whole board full of custom ICs and demodulate all the old legacy stuff. I would imagine this is what's really being used at Canberra.
3) There IS a newer (software based) receiver in the works, but not done yet
4) The processing load is substantially more than your old Dell can handle (we're talking about finding and demodulating a very, very faint signal that is a few Hz wide in a substantially wider bandwidth)
5) The interfaces to the analog RF hardware are somewhat unique.
6) Doing the processing requires a very stable reference clock (I assume your Dell doesn't have a hydrogen maser driving the on-mobo sound card? DSN receivers do.
7) There are a limited number of people in the world (probably 100) who really understand this stuff well enough to do the emulation, an even more limited number who are not retired, and a good fraction of them are busy working on #3, above.
Re:I've got an old dell they can use... (Score:3, Interesting)
I worked at bellsouth in '97; 1 of the midrange systems I was responsible for was a freaking ancient magnetic core drum & reel to reel monster that ran the switches that "a critical emergency system" used.
yes, you could replace the hardware components with something a little more modern, but you would have to be absolutely certain that the replacement component was exactly 100% the same as the legacy hardware, down to once-every-3rd-monday bugs; otherwise you could damage the system.
why not replace the whole thing? the company that made the system was out of business since the late 70's; no source for the software it was running was available, no complete logic diagram of the workings of the system. maybe it would have been possible, maybe not, but you are talking about a system that had been running without flaw for about 25 years. why replace it?
to the best of my knowledge, it's still running.
"News for Nerds"? (Score:3, Interesting)
It doesn't. Therefore /. must have made it into the "Mainstream Media" cabal.:-)
I don't know whether I should celebrate or commiserate. I fear the latter.
Anyway, anybody know what comps. etc are being used at the Tidbinbilla space tracking station?br I'm old enough to be genuinely interested.