test-drb

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101090 discussions

reforming capacitor tutorial/walkthrough

by aek＠bitsavers.org

"William Donzelli" <wdonzelli at gmail.com> wrote: > The caps from 1960s seem to be of little concern, and those from past > 1970 are of no concern. If the cap decides to die, its going to die. -- This was not the experience of the PDP-1 team during the restoration of that machine. Detailed records were kept of every cap that was reformed. This process took several months to perform. Blowing up a cap in the machine during restoration was not an option. Lyle, or one of the other hardware folks would know the details. I am disappointed at the 'let it just blow up' attitude that has been expressed on this list so far in the discussion.

18 years, 7 months

VAX 11/750 rescued, alas...

by RodSmallwood＠mail.ediconsulting.co.uk

The system key can be found on the key rings of many PDP11 enthusiasts. -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of J Blaser Sent: 08 October 2007 23:59 To: On-Topic and Off-Topic Posts Subject: Re: VAX 11/750 rescued, alas... Rod Smallwood wrote: > Hi > Fear not all is not lost. There's tons of modules around but not > that many cabs. > Yes, you are absolutely correct! The more I think about it, the more glad I am to have even this empty chassis. Definitely harder to come by than the modules that are missing. A few good souls have already stepped forward offering some help with the boards, so this revival might be less difficult than I anticipated at first. > In the picture of the Qbus board it appears to be sitting on the > module config diagram. > As it is pre printed and not filled in by hand its probably a standard > system. > That will give you a list of the boards. > Yup, I went through that last night. There is another label that was inside one of the front cover plates that does show a list of modules penciled in. So I believe I now know what the original configuration of this system was. I've come up with a minimum list of boards, and a wish-list of the boards that were originally included. Looks like the the mass storage was hung off of a UDA50, and some tape devices on the SI 9700 board (which I still am completely ignorant of). I have a couple of Fuji SuperEagles and an RA81, so I'll be on the lookout for SDI and SMD interfaces for the rebuild. I just hope the Fujis and RA81 are functional when the time comes! > Note of caution do not try to turn it on. The power supplies will need > some work. You need to reform/replace any electrolytics. > > Roger that! I'm a firm believer in a full chassis cleanup, capacitor reform, and separate PS checkout before every hitting the big switch on the front! ;-) Oh, yeah, that reminds me...I've got to locate the 'vending machine' power-switch key for this thing. Anyone know if it is a fairly standard key? > The case will clean up well and you can start off by getting the PSU's > working and getting the list of modules together. Disk drives would > have been in another rack I think. > This looks like it'll be a more lengthy revival than any that I've done up until now, which have been mostly qbus PDPs and uVAXen. A great winter project! - Jared

18 years, 7 months

1541-III group buy?

by dgriffi＠cs.csubak.edu

So, it seems to me that there is a decently sizable demand for 1541-III parts. I asked the creator of this thing if he plans to make PCBs any time soon. He said "no". But he left all the design files, firmware, etc on his website for anyone to use. So, how about a group buy? -- David Griffith dgriffi at cs.csubak.edu

18 years, 7 months

TI-990 ...

by bpope＠wordstock.com

I believe it was Chuck who was asking where to find TMS9900 and TMS9995 chips.. The TMS9900 is available from Unicorn Electronics for $34.88 each. See --> http://www.unicornelectronics.com/monthly.html Cheers, Bryan

18 years, 7 months

VAX 11/750 rescued, alas...

by RodSmallwood＠mail.ediconsulting.co.uk

Its not so much the age of the system more how long it is since it last ran. As minimum isolate the positive terminal and put a meter on ohms range across it. As the capacitor charges the resistance will rise. If it does then good if not or goes up slowly then change the capacitor. I rang our old (now retired) DEC branch field service manager and he said "Turn on a 750 stored for years and with no load on the PSU .. Sure use a pole about twenty feet long!!" Rod -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of Patrick Finnegan Sent: 08 October 2007 19:29 To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: VAX 11/750 rescued, alas... On Sunday 07 October 2007, Rod Smallwood wrote: > That will give you a list of the boards. > Note of caution do not try to turn it on. The power supplies will need > some work. You need to reform/replace any electrolytics. 11/750s aren't that old (early 80s), and shouldn't need reforming. It appears that William Donzelli agrees with me, and I'm sure he has more experience with this than I do. Pat -- Purdue University Research Computing --- http://www.rcac.purdue.edu/ The Computer Refuge --- http://computer-refuge.org

18 years, 7 months

reforming capacitors, worth it?

by wdonzelli＠gmail.com

> I think > Will's implying that the need to reform caps that new is not necessary, > because there's no data available to say that it actually does any good... One though occurred to me just a few minutes ago. Most failures in capacitors - actually almost all pre-IC components - can be boiled down to impurities getting into the innards of the part thru failing seals. This is documented in military and trade rags, as they found out in the jungles of the Pacific during World War 2. With capacitors, the problems seem to be the dielectric (oil) getting out (see my previous post concerning Vitamin Qs), or moisture getting in. Either way, the dielectric is poisoned near the weakest part of the cap's structure - the edge of the foil, specifically where the leads connect to the foil. I can not see where reforming an electrolytic capacitor will do any good for the seals. If the seals are drying up, cracking, shrinking, expanding, or in some way not meeting spec, the crap is going to get into the innards of the capacitor and lead to a failure. Other than a complete rebuild, I doubt any seals can be repaired. And if you are going to do a complete rebuild, you might as well run the cap until it fails. And unlike an inductors that can be baked to drive off moisture, capacitors do not do well in the oven. -- Will

18 years, 7 months

RS232 Breakout Boxes

by dkelvey＠hotmail.com

> From: dgriffi at cs.csubak.edu> > On Sun, 7 Oct 2007, Tony Duell wrote:> > > I can rememebr what 4 are :-)> >> > 1) An old RS23 breakout box. Real slide-switches to open all the wires,> > and 2mm sockets for cross-patching. The main signals are monitored by> > transistor-driven filament lamps, the whole thing is mains-powered,, said> > PSU also prvides +12V and -=12V outputs for forcing handshake signals> > ARRGG!!! You've provoked me into building a banana-jack breakout box!> Of course if you make one, put all the connector combinations on each side. Also put an extra connector on it that can be used to snoop the data in progress between two machines. One can usually put two receivers on a single drive. I've used this method to analyze unusual protocols in the past. It is handy. _________________________________________________________________ Climb to the top of the charts!? Play Star Shuffle:? the word scramble challenge with star power. http://club.live.com/star_shuffle.aspx?icid=starshuffle_wlmailtextlink_oct

18 years, 7 months

Apple again - Disk ]|[ this time...

by julesrichardsonuk＠yahoo.co.uk

Having got the Mitac A2 clone up and running (checked out the 80-column output today and that was fine - only casualty in the whole machine was one cap that had gone high-ESR), I've dug my Apple /// out of storage... Disk ]|[ question - should the ribbon cable to the internal drive be plugged into J2 or J3 on the drive's analog board (does it even matter)? A long time ago I disconnected mine as a precaution; the drive began eating disks, but I didn't have time to get to the bottom of it at the time - I suspect it just needs a good clean. I can't for the life of me find where I made a note of which socket the cable plugs into. Normally I leave myself a note somewhere in the machine for things like this, but for some reason I haven't with this one :-( cheers J.

18 years, 7 months

Setting up a VAXstation

by lproven＠gmail.com

Well, last night, I went and collected my first ever DEC box. It's a VAXstation 3100/38, bought on eBay for 99p (UK?0.99). It will be a few weeks until I get it home, and currently, it has no hard disks, but I'm hoping to rectify that. I plan to put 2 or 3 old SCSI disks in it - whatever I can find that will fit. I am sure they'll all be well under 1GB, as I believe that is a limitation for boot disks. I think I have a couple of 80MB ones around and maybe a 150MB or so. The two problems I don't currently have answers for are these. [1] I don't have a suitable monitor cable. I have a keyboard, 3 mice, and a DEC 17" mono monitor with a single BNC connector on the back. I also have a monitor cable, but it's an RGB one - one end is 3 colour-coded BNC connectors, the other is a D plug with three large shrouded sockets - like the larger connectors in a YB13 monitor cable but without the standard pins. On the back of the VAX is a monitor out port, but it's a D connector. Alas the machine is currently 15mi away or so, so I can't check, but I think it has about 20 pins. Again, a D connector. What sort of monitors will a VAXstation drive? I have an old Mac 21" monitor with a YB13 connector, which syncs happily enough to both PCs and Macs at around 1024x768, 1280x1024 (at a refresh rate of about twice a minute) and some Mac res in between - 1152x870 or so. Where on earth can I find a VAXstation video cable in 2007? [2] Friends have commented to me that a VAX of this age won't be able to boot from CD-ROM. Somewhere, I have a hobbyist VMS CD, if I can find it. It's been suggested to me that the easiest way to install would be to install VMS onto SIMH on my PC, netboot the VAXstation off the simulated VAX and install from one to the other. This sounds moderately hairy to me. I'm not a VMS virgin but I've not used it in 15y or so and I've never installed a machine from scratch - I just did day-to-day sysop duties. Is this likely to be correct? That a 3100/38 won't be able to boot >from CD? If it can, what sort of CD-ROM drive will I need? Do I need the special 512KB block support that SPARCstations are supposed to need? I have an old external Apple drive (CD300, I think) that I hope will do, if I can come up with the right permutations of SCSI cables to connect it... -- Liam Proven ? Profile: http://www.linkedin.com/in/liamproven Email: lproven at cix.co.uk ? GMail/GoogleTalk/Orkut: lproven at gmail.com Tel: +44 20-8685-0498 ? Cell: +44 7939-087884 ? Fax: + 44 870-9151419 AOL/AIM/iChat: liamproven at aol.com ? MSN/Messenger: lproven at hotmail.com Yahoo: liamproven at yahoo.co.uk ? Skype: liamproven ? ICQ: 73187508

18 years, 7 months

TI 990 architecture / was Re: TI-99/4A Floppies

by ajp166＠bellatlantic.net

> >Subject: Re: TI 990 architecture / was Re: TI-99/4A Floppies > From: Dave McGuire <mcguire at neurotica.com> > Date: Wed, 03 Oct 2007 12:48:37 -0400 > To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> > >On Oct 2, 2007, at 3:47 PM, Martin Scott Goldberg wrote: >>> There are really three 99/4 home computers, original with chiclet >>> keys, the >>> second and most common with a really nice keyboard and the whie >>> version that >>> is really the same thing with a few board level cost reductions. >> >> Actually, there's one TI-99/4 and two TI-99/4a models. > > What are the differences between them, does anyone know offhand? > > -Dave There are really three 99/4 home computers: original with chiclet keys the 99/4 the second and most common with a really nice keyboard 99/4a the white console version that is really the same thing with a few board level cost reductions. (still 99/4A on the back) Allison

18 years, 7 months

SGI Onyx Power Boards & System Controller

by jplist2007＠kiwigeek.com

Greetings all; I picked up an SGI Onyx 10000 RE2 rack ("Terminator") last week from surplus and, unfortunately, it appears I'm in the same boat as J Blaser - Boeing used this machine as 'parts' for another. I'm missing the Power Boards (I believe I need three) and the System Controller. Also someone removed the Graphics and Main I/O panels... violently, apparently, as the cable that goes from the DG2 (Display Generator) to the breakout has part of the breakout PCB still attached to the cable! I see a main I/O panel on eBay right now relatively inexpensively, as well as the graphics panel - but the Graphics I/O Panel is for an InfiniteReality, not a RealityEngine2, and is no good to me, alas. Many thanks to all; JP Hindin

18 years, 7 months

reforming capacitor tutorial-walkthrough.htm

by lynchaj＠yahoo.com

>Has anyone got one online? If so, URLs please... [snip] Here is a good one: http://www.s100-manuals.com/Repairs.htm I can't say if it is effective or not but I have followed the directions using a variac several times with some success. At least no exploding/leaking electrolytics in any of my restored machines. I have seen some equipment with burst/leaking electrolytic capacitors and they are very messy. Even if the procedure is marginally effective, it is probably worth something. Preventing even one burst capacitor saves you a *LOT* of time cleaning up. Best of luck! Andrew Lynch

18 years, 7 months

these RTL or what?

by ajp166＠bellatlantic.net

> >Subject: Re: these RTL or what? > From: woodelf <bfranchuk at jetnet.ab.ca> > Date: Mon, 08 Oct 2007 12:11:23 -0600 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Allison wrote: > >> RX02 works with PDP-8, WD1793 works with Cmos6120 (PDP-8), VAXen and >> other long word machines are using floppy and other 8bit interfaces. >> VAX 780 microcode was loaded from floppy. > >I grew up in alas in a PC world.I got to play with a 8 but that >is about all. I'd have guessed that. ;) > >> Most of those systems had already dealt with the 8bit/n-bit issue >> and as devices got larger and space less an issue it became less >> an issue. If it were, then PCs would have 32bit wide HDC rather >> than 16bit. > >I like 16 bits for IDE ... You can cut that down to say 12 bits for >your PDP-8. 9 or 12 bits for the cpu depending on what cpu I build.:) True. But since the 386, PCs are 32bit, for that fact since 1978 VAX was 32bit.. You would have thought a wider IDE or data channels would have happend. But it hasn't. IO devices often lagged the CPUs or were designed for the devices convenience or so it seemed. I feel legacy, (not always PCs) played distinct factor as well. Allison

18 years, 7 months

these RTL or what?

by ajp166＠bellatlantic.net

> >Subject: Re: these RTL or what? > From: woodelf <bfranchuk at jetnet.ab.ca> > Date: Sun, 07 Oct 2007 08:49:56 -0600 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Allison wrote: > >> Does it really makes that much differnce the number of bits for a char? >> Really, Six bits was kinda tight for work where upper or lower case >> was used but it didn't affect calculating Pi to a 100 places. >> Wasn't the basic chunk 9 bits for PDP10 and it happened (DEC >> software) used 6 bit char notation as a carry over from earlier >> life with friden flexowriter and TTYs on earlier machines? > >Floppy disk is 8 bit I/O. That made all the difference when standard >floppy disk controlers came out. Ben. RX02 works with PDP-8, WD1793 works with Cmos6120 (PDP-8), VAXen and other long word machines are using floppy and other 8bit interfaces. VAX 780 microcode was loaded from floppy. Most of those systems had already dealt with the 8bit/n-bit issue and as devices got larger and space less an issue it became less an issue. If it were, then PCs would have 32bit wide HDC rather than 16bit. With that character representation and word size are at best only loosely associated or an OS convention. If anything ASCII was a standard as were a few others like IBMs scheme. Converting >from one coding to another was one of the first apps (code breaking). Going from one character representation to another is generally is not a big task so long and it's not language translaton. We as early users did that often for devices like Seletric printers. Did character convention used affect system choice or OS choice, possibly. It was only a piece of a larger picture of how systems evolved. Allison Allison Allison

18 years, 7 months

these RTL or what?

by ajp166＠bellatlantic.net

> >Subject: Re: these RTL or what? > From: shoppa_classiccmp at trailing-edge.com (Tim Shoppa) > Date: Sat, 06 Oct 2007 08:40:15 -0400 > To: cctech at classiccmp.org, cctalk at classiccmp.org > >Allison <ajp166 at bellatlantic.net> wrote: >> In the end ECL was a way to speed but always at such a high system cost >> and complexity it was often behind the curve for integration and delivery. > >It depends on what you're doing. > >ECL was perfect for custom-built lab and military hardware. Follow >a few simple rules and even a bozo like me could reliably lay out the >PCB's. Contrast that with 74F technology where you couldn't even figure >out if ground at the center of the board was the same as the ground at >the edge of the board :-). Having used most logic from transistors to ECL100k and some oddballs inbetween I'd agree. ECL was excellent for mixed signal and fast front end stuff. My favorite uses were programable /n for PLLs and frequency counters. ECL was far nicer without ground noise and some of the transmission line difficulties that the faster/fastest TTL (and CMOS) were really nasty driving. Ringing and reflections on a board, bus or interconnect could really ruin your day. That made ECL nice for fast intersystem connects were the cables were for reasons coaxial cables or other shielded schemes. >Above the onesies-twosies level things weren't so clear. There's a big >leap between a back-projector or array-processor made at the onesies-twosies >level and the world where VLSI becomes economical. Gate arrays helped >span this gap but that gap had been pinched to nonexistence by the mid-80's. The magical thing that really impacted logic design indirectly be it discrete transistors or the fastest of the fast was simply size. The faster the logic was the closer all the sourrounding bits had to be to capitalize on it. Otherwise the rule of thumb of 1nS/ft took over never minding load capacitances. Witness the Cray round machine (YMP?). There is a long history of systems compaction, cooling and speed interactions in computers. >Minicomputer makers like DEC who also had their own fabs were in an odd boat... >the process-leading CPU chips couldn't utilize the fabs built to >deal with them because DEC didn't sell enough CPU's. In the end >a vast army of interface and peripheral chips seemed to keep things >churning well enough that they kept their fabs for many many years past >where I was convinced they couldn't be economically viable. Bingo there. While a few chips were economically successful it was only with the help of silicon foundries like WD, SMC and AMD to get needed volumes. In the end the greatest value of silicon hill was in its sale with a few licenses kicked in. Allison

18 years, 7 months

MFM or ESDI QBUS controller for one PDP-11/23 PLUS

by spedraja＠gmail.com

Hello. As the subject say, I'm searching for one working MFM (not RQDx, better something like the Andromeda UDC) or ESDI QBUS controller plus cables to use with one PDP-11/23 PLUS. The ESDI would be a better choice because I have one 300 Mb HD and one 700 Mb HD, both of full-height (in the terms used with old PeeCee's). I have too a couple of RX33 floppies but no controller for them. I would appreciate to obtain one. Finally, I am thinking in use one old PC enclosure for disks and floppies. Someone has did it ? Results ? Can contact privately with offers. Thanks and Greetings Sergio

18 years, 7 months

reforming capacitor tutorial/walkthrough

by legalize＠xmission.com

Has anyone got one online? If so, URLs please... -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

18 years, 7 months

Setting up a VAXstation

by ajp166＠bellatlantic.net

> >Subject: Re: Setting up a VAXstation > From: shoppa_classiccmp at trailing-edge.com (Tim Shoppa) > Date: Mon, 08 Oct 2007 08:14:33 -0400 > To: cctech at classiccmp.org, cctalk at classiccmp.org > >Tony Duell said: >> I cna understnad why people are interested only in old software, not >> hardware, and want to run it under emulation on a modern machine >> >> My puzzlement is with people who want to run the old hardware (not have >> to run the old hardware becuase it is part of some machine tool or >> something) but don't want to understand what's going on inside. What more >> do you get over running the software under emulation? > >In fact, availability of hardware is a huge factor in succesfully >making an emulator for a machine. All but the simplest processors >are complicated enough that there are little corner cases all over >the place where none of the processor/architecture documentation tells >you what is going to happen. > >And outside the central processors, all peripherals but the very simplest >are filled with complicated and undocumented behavior. > >Schematics could answer many of these questions, but in real life >they end up guiding the search for the answer to the question rather >than being the actual defining source for the answer. > >So in general emulator users and especially developers completely >grok the need to have hardware working. Sometimes I believe that >today's emulator developers know much more about the architectures >than the original architects did :-). (In a couple cases, they are >the orignal architect!) > >Availability of software is also important for making a reliable emulator. >You could spend years reading the books to write an emulator, but you >don't trust anything you've read or done until you've booted the simplest >OS. > >Tim. The best example of this that comes to mind is the Apollo Guidence Computer (AGC). There was one hardy and persistant soul that not only researched it, he built a sim and tracked down samples of software to validate the sim and the later hardware. One great issues was lack of documentation, apparently much was lost/destroyed when that chapter of the space program ended around 30 years ago. The few intact copies of the AGC (Apollo command modules) likely haven't seen power in at least that long if even complete. I doubt any of the CM holders could be convinced to power it up assuming they were even preserved sufficiently to safely do so. So for those interested in machines that are obscure, unusual or very rare even generating a sim has to be a huge challenge only equaled by task of gatherering the needed data to base it on. It is reverse engineering on a very deep level for a faithful sim. Allison

18 years, 7 months

these RTL or what?

by ajp166＠bellatlantic.net

> >Subject: Re: these RTL or what? > From: "William Donzelli" <wdonzelli at gmail.com> > Date: Sun, 07 Oct 2007 15:55:57 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >> Yes, but conductors on substrate are slower depending on substrate used. >> They are dense but TCMs still have to talk to other TCMs. > >So you have never seen the innards of a 3081, then? Not enough of one to appreciate. I do know that IBM did some fairly sophisticated stuff to get around the problem. Allison >-- >Will

18 years, 7 months

Setting up a VAXstation

by RodSmallwood＠mail.ediconsulting.co.uk

My view is that if you have spent little or nothing on the computer. Then a few pounds on a cable is a good investment. If you do not have experience in making up cables then don't waste time learning for a small number. Rod -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of Pete Edwards Sent: 03 October 2007 14:34 To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: Setting up a VAXstation > > > here, folks. I'm not going to spend ?20 or ?30 on getting or making > > a cable for a 99p computer! > > Ah, that's right - you're in the UK so the telephone cables won't be > the same. Actually, you _might_ be able to take an Ethernet cable, > file off the clip and file both sides to make it fit. If you can keep > the pins centered properly after filing, it should work. > > -Ian > There's plenty of telephone kit in the UK that does use RJ11, look on answering machines and especially external modems - they nearly always came with an RJ11-BT adaptor cable. A lot of modern laptop internal modems seem to have RJ11 sockets too. -- Pete Edwards "Prediction is very difficult, especially if it's about the future" - Niels Bohr

18 years, 7 months

these RTL or what?

by ajp166＠bellatlantic.net

> >Subject: Re: these RTL or what? > From: woodelf <bfranchuk at jetnet.ab.ca> > Date: Sat, 06 Oct 2007 18:10:55 -0600 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >William Donzelli wrote: > >>> Crunching numbers was a part of the task. The other part was moving >>> and handeling data in mass storage and memory. Most of the DEC hardware >>> moved data pretty fast. What was the demise of PDP-10 was simple, megabytes. >> >> And being six bit machine in an eight bit world... >> >SEVEN bit world. We can blame IBM for all our 8 bit PC ASCII stuff. >Eight bits I think for EBDC was earlier. Having 4 bit sized TTL stuff >does not make for nice octal digits. Ben. Does it really makes that much differnce the number of bits for a char? Really, Six bits was kinda tight for work where upper or lower case was used but it didn't affect calculating Pi to a 100 places. Wasn't the basic chunk 9 bits for PDP10 and it happened (DEC software) used 6 bit char notation as a carry over from earlier life with friden flexowriter and TTYs on earlier machines? While It may have been an issue and part of the picture I don't feel it was as heavy a weight as VAX was easier to promote and potentially could address Gigabyte size memories with 32 bit pointers rather than 256KW with a memory extension to 4MW. I find it easier to see and recognize that bigger machines with bigger memories for big programs crunching huge amounts of data is what had a big part in the 10s demise. Only opinion but hey, it's free. Allison

18 years, 7 months

these RTL or what?

by ajp166＠bellatlantic.net

> >Subject: Re: these RTL or what? > From: "William Donzelli" <wdonzelli at gmail.com> > Date: Fri, 05 Oct 2007 13:55:28 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >> Using ultra-fast ECL doesn't make much sense when you've got nanoseconds >> of delay to the backplane, to the next board, and back to the part that >> needs the signal. > >That depends on how tight everything is. Thermal Conduction Module, anyone? At 1ns/ft even the TCMs were not tight/dense enough. >> The ECL technology used in the VAX9000 was gate arrays with roughly the >> same timing parameters as 100K ECL (0.5 to 1.0 ns propogation delays). > >Yes, but I do not think that was the cutting edge anymore. Considering >the 9000 was supposed to be the machine that finally convinces the >mainframe world to accept DEC, it may have been a poor choice. We >probably will never know. 9000 may have been as big of an >embarrassment as the KC10. > >Even though the 9000s were bombs, they are one of the few VAX machines >I would chase after. ;) the problem is the 9000 by time it got out the door CMOS system on a chip was around the corner. With the ability to put transistors literally next to each other it was easier to achieve overall speed. When you consider that you could put multiple systems in less space than a 9000 well, quantity has it's own special quality. >> Responsiveness of a computer system depends on a lot more than the >> speed of the semiconductors used to build it. Plenty of modern examples >> of how to make fast silicon seem slow are coming out of Redmond I >> notice :-). ;) I was always amazed that a dozen users could be on an 11/34 but one user could bring a 486 to it's knees. > >I am thinking raw horsepower - all the benchmarking stuff. Looking at >the KL10 (or the other DEC ECL machines), it justs seems like they >should have been better number crunchers. Crunching numbers was a part of the task. The other part was moving and handeling data in mass storage and memory. Most of the DEC hardware moved data pretty fast. What was the demise of PDP-10 was simple, megabytes. A PDP-10 could not address the huge volumes of data in one chunk comming >from the more complex models and programs in use. VAX offered a 32bit address, PDP-10 was basicially 18bits with memory extension. If your munching a model or database of millions of elements that is as important as the time to add two word size numbers. It's why PDP-11 was replaced with VAX and why VAX was replaced with Alpha. In the end ECL was a way to speed but always at such a high system cost and complexity it was often behind the curve for integration and delivery. Usually other technologies were close enough behind and had the higher density or ease of integrationin to larger systems needed to offset the per gate speed with sometimes better complex function speeds. Allison >-- >Will

18 years, 7 months

Fw: Software Find at Thrift

by jrkeys＠concentric.net

Second try at sending this to list. ----- Original Message ----- From: "Keys" <jrkeys at concentric.net> To: "cctalk at classiccmp" <cctalk at classiccmp.org> Sent: Friday, October 05, 2007 8:51 PM Subject: Software Find at Thrift > While checking out a old hangout I found a copy of IBM's Hollywood > software Version 1.0 (on 3.5 FD), complete in the box for $1.81 plus tax. > There was not much else there like it was in the long ago past. Speaking > of Hollywood, the Hollywood video store near us is closing and I went > dumpster driving the other night and found that they had tossed all the > video game cases that had been on display. Most but not all were empty, I > found PS2 and PS3 DVD's in some of the cases. It got too dark and I had to > stop pulling cases from the dumpster but there was over 150 cases left in > the trash. > > John

18 years, 7 months

Test Only No Message

by jrkeys＠concentric.net

TESTING

18 years, 7 months

these RTL or what?

by ajp166＠bellatlantic.net

> >Subject: Re: these RTL or what? > From: "William Donzelli" <wdonzelli at gmail.com> > Date: Sat, 06 Oct 2007 16:48:07 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >> >That depends on how tight everything is. Thermal Conduction Module, anyone? >> >> At 1ns/ft even the TCMs were not tight/dense enough. > >Have you ever seen a IBM TCM? Yes, but conductors on substrate are slower depending on substrate used. They are dense but TCMs still have to talk to other TCMs. >> Crunching numbers was a part of the task. The other part was moving >> and handeling data in mass storage and memory. Most of the DEC hardware >> moved data pretty fast. What was the demise of PDP-10 was simple, megabytes. > >And being six bit machine in an eight bit world... ;) minor thing. >-- >Will

18 years, 7 months

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