On Friday 09 June 2006 09:29 pm, Jay West wrote: I think you're probably right, which goes a ways towards explaining why I feel so at home here. :-) Though I don't tend to insist on it any more, I got tired of that beating-your-head-against-the-wall feeling. But it's definitely a preference, when such stuff is even possible these days. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, a critter that can be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

Dan Williams wrote: I suspect that the faster devices with sub-micron technologies will *die* before then (EM, etc.). Yet another reason for running older/slower hardware?? :>

Jules Richardson wrote: Has anyone any "real" data on EM effects? Or is this effectively urban legendry?

jim stephens wrote: IIRC, early EPROM technology was ballparked at ~10 year lifetime. I always wondered how much of that was influenced by light leakage into windowed devices and how OTP devices would compare... <grin> Gee, I wonder *why* they were doing that? ;-)

jim stephens wrote: <grin> I was alluding to the significance of radhardening for military applications :> Ah! I guess there *are* some "peaceful applications"! :>

Don Y wrote: Good question, and no I haven't. I'd breathe a sigh of relief if it weren't true I suppose - it's sad to think of the effort of keeping these things running if they're going to naturally fail despite best efforts a few years down the line. Isn't chip death something to do with natural Brownian motion or something? Eventually things just move around to the point that the chip stops functioning - whether it's been powered or not. I'm not a physicist - just dimly-remembered classes from years ago (and being told the 50 year figure) (I'm sure if it *is* true then the 50 years is something a guesstimate or worst-case, and lots of things will last much longer than that)

I have read in several places (industry papers and the like) that hot-carrier injection does cause localised damage that eventually leads to failure. But even if the effects have been exagerated, solid state Diffusion is real and will kill a chip even if it is never powered up. What I don't know is whether the problem will show up in 10 years, 100 years or 1000 years. Antonio -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.0.394 / Virus Database: 268.8.3/362 - Release Date: 12/06/2006

Don Y wrote: Moore's law ... Techology doubles every 18 months. More Law ... Sales of computer have to double every year. :(

Yes, OK, I don't insist on the service manual being available. If the thing is standard components, and not too many of them, it's not hard to trace out a schematic. But then again, if the product is a couple of ASICs, with no docs, I am going to avoid it. As I've said before, I am not rich enough to buy cheap tools (and I use 'tools' in the widest sense here). Yes, there are, of course, products that I know I will have to replace. Like primary cells. And secondary cells (they have a limited number of recharge cycles). And the toner cartridge in my laser printer (although I would be annoyed if some mechanical part of that cartridge failed before all the toner was used up. I also might try refilling it, particularly if it was a hard/impossble-to-obtain one for a classic printer). PC keyboards, though, I do repair. Normally becuase they fail at an inconvenient time (like on a satruday evening), and I can repair them sooner than I can get a replacement. -tony

I know!. Even I don't normally do it, but I have taken old cartridges apart as part of figuring out just how the laser printer in question works ('Aha, that contact goes to the primary corona wire, that one to the drum gronnd', etc). I would consider rebuilding a cartridge if it was for a classic laserprinter for which cartridges were no longer available (like 'homebrew' [1] Canon CX-VDO on my PERQ) [1] This printer started out as a Canon LBP8-A1. A PAL chip (actually a HAL, which is a mask-programmed PAL) chip on the formatter board failed. Canon don't supply service information or parts (I later found I could have got a complete replacement board, but I doubt I could have afforded it). Anyway, thanks to Bob Davis and others, I found out that the PERQ could take a direct-drive ('video interface') laser printer that was based on the same engine. I managed to get an assortment of part-stuffed PERQ interface cards and the schematics for that, assembled one fully, took the printer apart into very little pieces, worked out how that worked, matched up signals, made cables, etc. And finally put it all together. No it didn't work. But it nearly did. After a bit of tracing, I found I'd missed a jumper wire off the interface board. Fitted that, it worked fine. After all that work, you can bet I am going to try and keep that going. It's like my HP45 calculator. That's a common-ish model anyway, and mine is worthless to a collector, it's got half the legends rubbed off, not all the display digits are the same size, the batter contacts are corroded, etc. But I built that machine from bits a friend was giving away -- A&R chip from one board, other chips from another board, PSU converter transsistor from the junk box, and so on. As such, it means a lot to me. It's time for the story fo the toner and the toilet :-). A friend of mine has an SX-engined printer, and he managed to convince me to show him how to take the cartridge apart (I'd already one one of mine, so I knew what came off in what order). Anyway after removing the outer casing and separaing the 2 sections from the drum, we came to the waste toner collector. And he decided to empty it -- into the toilet. It was at this point we discovered that toner floats on water, and wouldn't flush away. Fortunately, one of us had the idea to add washing up liquid. That produced the most amazing black foam that finally did flush away. Depends on what's wrong with them. One of mine died when a PSU fell onto it. The PCB was crackd into several pieces. Amazingly there was a schematic on the box it had some in, which I'd cut out and filed, but it was incorrect (keys were not where they were shown in the matrix). That took an evening to sort out! -tony

der Mouse wrote: Heh heh heh... friend dropped her TV (in 1987). I got the call: "Can you fix it?" The corner of the PCB that supports the flyback had snapped right off. Thankfully, nice big foils so laying "untwisted" stranded wire across each broken land with a *big* soldering iron (to heat up all that extra Cu) solved that problem. TV is running to this day! ;-)