[cctalk] Re: Paper tape in casettes...
Hi Paul, thanks for your answer and the interesting links... > > Aha, interesting! Did a short search, but have not been able to > > find a picture of a casette. Just a pile of paper tape instead ;-) > > > > https://images.app.goo.gl/HYqkpYHJUxZeGfiA8 > > Bitsavers has a collection of G-15 manuals. For a picture of an > open cassette, see PDF page 27 in > http://bitsavers.org/pdf/bendix/g-15/60061400_G15D_Parts_Manual.pdf. Ahh OK, I see. But that is not a hermetically sealed casette suitable for outdoor use in windy, rainy weather like the one on my desk. As the thread deviated meanwhile, I guess the Elliott Mylar tape casette is a unique leftover from the old days ;-) Best wishes, Erik. ''~`` ( o o ) +--.oooO--(_)--Oooo.-+ | Dr. Erik Baigar Inertial Navigation & | | Salzstrasse 1 .oooOVintage Computer | | D87616 Marktoberdorf ( ) Oooo.Hobbyist / Physicist | | e...@baigar.de +--\ (( )---+ | www.baigar.de| \_)) / +--+ (_/
[cctalk] Paper tape in casettes...
Hi there - recently I posted a small video on a rugged paper tape casette... https://www.youtube.com/watch?v=O2jnThYsPKc I wonder whether anyone kows if someone else had the idea of putting paper/mylar tape into a casette for repeated use e.g. to load an OS or similar. Best wishes, Erik. ''~`` ( o o ) +.oooO--(_)--Oooo.---+ | Dr. Erik Baigar Inertial Navigation & | | Salzstrasse 1.oooO Vintage Computer | | D87616 Marktoberdorf ( ) Oooo. Hobbyist / Physicist | | e...@baigar.de +\ (( )-+ | www.baigar.de| \_)) / +--+ (_/
[cctalk] Re: Tadpole RISC laptop RAM modules
> Izzat a "SPARCBook II"? If so, I have one with 2 drives, and > the /usr drive is failing. I can replace that but I have no > idea how to reinstall SunOS/Solaris/Whatever. I did that in the past using a network install. One will need ftfp (for kernel) and bootp (for parameters and paths) as well as old style nfs on a server with the installation media. Worked nicely and is pretty fast if CDs are copied to harddrive before- hand... Best wishes and good luck, Erik. ''~`` ( o o ) +--.oooO--(_)--Oooo.-+ | Dr. Erik Baigar Inertial Navigation & | | Salzstrasse 1 .oooOVintage Computer | | D87616 Marktoberdorf ( ) Oooo.Hobbyist / Physicist | | e...@baigar.de +--\ (( )---+ | www.baigar.de| \_)) / +--+ (_/
[cctalk] Re: SGI vs. Mac
Hi There! An Indy for instance, is it much faster then a similarly clocked PowerMac? What about an Indigo 2 IMPACT 1. Does that blow most PMs away? Hmm, never used MACs of that generation. Graphics performance of the SGIs was awesome for its day. Still using an Octane (2*R12k) from time to time with old software I compiled for it and very impressive still is the responsiveness of the OS: Most other OSes still today let you feet that there is load on the CPU. With the SGIs you do not feel that so much if working in a terminal for example. I also have got dual monitors, video compressor and crystal eyes on the Octane ;-) Octane greatly improved in memory performance (well above GB/s) over the earlier SGIs and I lot of other competitors... Unfortunately my maxed out Indigo2 suffered a maniboard failure recently and does not boot any more... Best wishes and merry Xmas, Erik. ''~`` ( o o ) +.oooO--(_)--Oooo.---+ | Dr. Erik Baigar Inertial Navigation & | | Salzstrasse 1.oooO Vintage Computer | | D87616 Marktoberdorf ( ) Oooo. Hobbyist / Physicist | | e...@baigar.de +\ (( )-+ | www.baigar.de| \_)) / +--+ (_/
Re: 400 Hz
Applying a square wave of 15kHz has harmonics up to 100kHz and more. That means, that the current in these is more than 100 times bigger - BAM! Additionally, output devices with really fast switching times can trigger reflections back from the load, and these can potentially expose these devices to very high reflected voltages, which will trigger their breakdown.? Yes, can definitively happen. The small modern ones with the digital DSPs recognize this and get an error message, but bigger ones might noch have enough time before failure! Good input Carlos! ''~`` ( o o ) +.oooO--(_)--Oooo.--+ | Dr. Erik Baigar Inertial Navigation & | | e...@baigar.de .oooO Vintage Computer | | www.baigar.de( ) Oooo. Hobbyist | +---\ (( )+ \_)) / (_/
Re: 400 Hz
k Note that VFDs are designed to run motors exclusively. They approximate a sine wave with pulse width modulated 400 V pulses. DON'T EVER try to run electronic gear with a VFD, at least without a massive Yes, that is what I suggested; these filters are called "Sinus Filters" in the field of driving even motors over longer cables. One does not want to transmit the 10kHz PWM over longer distrances. I've heard that. But why? It's not like the electronics we're talking about actually runs on AC. (a) Input filters often contain caps... https://uk.tdk-lambda.com/content/faq/130796117766108286_FilterFAQ_how%20Image%201.jpg With 50Hz or 60Hz they create a little current which does not hurt. Applying a square wave of 15kHz has harmonics up to 100kHz and more. That means, that the current in these is more than 100 times bigger - BAM! Instead, it goes right into a transformer (an inductive load not much different from a motor) (b) Yes, a transformer usually has an optimum frequency range. Above it does not deliver the energy to the output. Why? (1) Because of stray inductivity. That is what helps you in filtering ther higer frequencies. But there is also (2) capacity between windings shorting the higher frequencies -> Heat and stress for the insulation. And finally (3) each time you are changing the magnetic field in the core, it causes loss and heat. The more often one tries to do that, the more loss -> Additional heat. Summary: Depends on the transformer what happens. May be OK, may fail after some time duer to heat or the insulation may break down. and after that into a ripple filter. That filter IS the "massive smoothing filter" you're talking about. (c) After the rectifier, you have got the caps. They are no problem, but the rectifiers (e.g. 1N4007 or similar) are optimited for lower frequencies. They to not like higher frequencies: Esp. seitching them off causes some current in the wrong direction eventually heating the diode. May be a problem, but have not had trouble with this case yet... The voltage issue is a different one. I've never seen a VFD that offered anything other than frequency change -- indeed, it produces the same RMS output voltage as what you feed it, and it isn't insulated. Look to the link in my other email. The device there is around USD100 and you can select frequency (10..400Hz) and Uout (10%...100%) and also go ramps etc. Again good luck ;-) Erik. ''~`` ( o o ) +.oooO--(_)--Oooo.--+ | Dr. Erik Baigar Inertial Navigation & | | e...@baigar.de .oooO Vintage Computer | | www.baigar.de( ) Oooo. Hobbyist | +---\ (( )+ \_)) / (_/
Re: 920M - an European contemprary of the Apollo Guidance Computer
Hi Marc, Quite impressive indeed! I did not know of these machines. Thanks for your feedback - yes, although more than 700 made, they are quite rare. Took almost 10 years to get hands on one of the 920Ms which where also ahead of time in 1966... Erik. ''~`` ( o o ) +.oooO--(_)--Oooo.--+ | Dr. Erik Baigar Inertial Navigation & | | e...@baigar.de .oooO Vintage Computer | | www.baigar.de( ) Oooo. Hobbyist | +---\ (( )+ \_)) / (_/
Re: 920M - an European contemprary of the Apollo Guidance Computer
Some additional remarks: The 920M is par of the 900 Series from Elliott (later Elliott Automation, GEC Marconi Avionics, BAe Systems) ...maybe interesting to note, that apart from the 18bit 920M and related machines, there is a series of 12 bit ones which have a simmilar (but not identical) instruction set. ...even one member of the family had 13 bits. ...these machines where used in applications, where accuracy was less important (autothrottle compputers, air data systems) and size/weight/power consumption was paramount. Sorry, by accident the footer from my work email was with the first posting - all the project is entirely hobby work and not related to the business I am working for... That is my private signature ;-) ''~`` ( o o ) +.oooO--(_)--Oooo.--+ | Dr. Erik Baigar Inertial Navigation & | | e...@baigar.de .oooO Vintage Computer | | www.baigar.de( ) Oooo. Hobbyist | +---\ (( )+ \_)) / (_/
920M - an European contemprary of the Apollo Guidance Computer
Dear colleagues in vintage computing ;-) In the last years there has been substantial interest in the Apollo Guidance Computer (AGC). So maybe someone might be interested what happened outside of the United States in the 1960ties: Over the last few years I restored a 920M computer which was (among others) used as the guidance computer in the Europa rocket. This was the ancestor of the European Ariane sapce launcher: https://en.wikipedia.org/wiki/European_Launcher_Development_Organisation Although not well known, this machine is a contemporary of the AGC, it also uses integrated, SMD mounted circuits and is realized in DTL techology (Diode Transistor Technology). Its word width is 18bit, 8k of core store where standard within a show-box sized chassis. 2us and later down to 1us instruction time where stadnard. In contrast to the AGC, this machine was a member of a whole series of airborne computers - some of which are still in use TODAY (2021). After core and the DTL chips became obsolete, this architecture even was re-implemented by BAE systems using the AMD29XX chipset in the same chassis as drop-in replacement. The 920M never had core rope memory, and for rocket guidance 8k have been enough although adding a 2nd box extending the core was possible. Tte architecture is able to support up to 256k words of 18 bit. Of course, the instruction set is very archaic - no carry flag, no stack but it served its purpose with 18 bit choosen as the perfect word length to give reasonable resolution without need for double-word calculation in most applications; http://www.programmer-electronic-control.de/Elliott920FactsCard.pdf If this triggered some interest, you may watch my recently released video on the 920M (covers applications, internals and some software is shown running)... https://www.youtube.com/watch?v=v-gF5g0nnoE ...or visit my project page regarding the work of restoring three different members of this computer family to working condition: http://www.programmer-electronic-control.de/index.html Happy computing to all of you, best wishes, Erik. P.S. Just wanted to point out, that also in Europe there have been relevant developments regarding spaceborne computing in parallel to the Apollo programme! In no ways I want to diminish the achievemets of the Apollo development team... ''~`` ( o o ) +.oooO--(_)--Oooo.--+ | Dr. Erik Baigar Inertial Navigation & | | e...@baigar.de .oooO Vintage Computer | | www.baigar.de( ) Oooo. Hobbyist | +---\ (( )+ \_)) / (_/ Dr. Erik Baigar Scientific Lead Spectroscopy Systems Technologie Team Spectroscopy THORLABS GmbH M?nchner Weg 1 85232 Bergkirchen Germany Tel.: +49 (0) 8131 5956-40147 Fax.: ?+49 (0) 8131 5956-99 Mail: ?ebai...@thorlabs.com Web: ?www.thorlabs.com General Manager: Dr. Bruno Gross HRB No: 85345, M?nchen
Re: Rolm computers
Hi Peter, sorry I have no items to pary with. Just trying to preserve the legacy of the early Rolms by keeping one unit up and running and having some spares. Anything special you are looking for (a 1666B is for auction on eBay right now)? Best wishes, Erik. Am 22. Oktober 2018 12:28:34 GMT-06:00 schrieb Peter Van Peborgh via cctech : >I would be interested in any Rolm items you might have. (no promises.) > >Thanks, > >Peter VP > >|| | | || | | || >Peter Van Peborgh >62 St Mary's Rise >Writhlington Radstock >Somerset BA3 3PD >UK >01761 439 234 >|| | | || | | || -- Diese Nachricht wurde von meinem Android-Gerät mit K-9 Mail gesendet.
Re: Rolm Computers: 1602, 1602A, 1602B, 1666, MSExx (was Data General Nova Star Trek)
Hi Bill, thanks for your reply. It would be cool to see this brochure - can you put it on a scanner? So you did not work with those yourself? Thanks again, Erik. Am 22. Oktober 2018 08:38:14 GMT-06:00 schrieb Bill Degnan : >While we are on the subject of Rolm I was curious and found in my docs >library a Rolm 1601 Sales brochure with some tech info/parts/prices. >Heavy >duty machines for sure. >Bill > > >On Sun, Oct 21, 2018 at 2:25 PM Erik Baigar via cctalk < >cctalk@classiccmp.org> wrote: > >> >> Hi Paul, thanks for your reply - good to see that there are still >guys out >> there who worked with this heavy iron. So you have been in the UK >while >> working with the Rolm? I guess it was a 1602B or later and pesumably >some >> airborne early warning stuff? Best wishes, Erik. >> >> Am 21. Oktober 2018 03:12:52 GMT-06:00 schrieb Paul Anderson via >cctalk < >> cctalk@classiccmp.org>: >> >I was at the DG factory school at Southbourgh in 76 or 77, and >worked >> >on a >> >ROLM NOVA while at RAF Chicksands in the late 70s. Unfortunately, my >EX >> >through out all of the manuals, prints, etc along with a complete >set >> >of >> >SAGE (ANFSQ-7) docs. >> > >> >Paul >> > >> >On Sun, Oct 21, 2018 at 3:38 AM Thomas Hollowell via cctalk < >> >cctalk@classiccmp.org> wrote: >> > >> >> Hi Eric, >> >> My name is Tom Hollowell. I took the US support of Rolm in 1998. >PWA >> >> assumed the international. I noticed that you have some ROLM >> >hardware. I >> >> may be interested in finding out what you have. >> >> Let me know, >> >> Thanks, >> >> Tom >> >> >> >> Sent from my iPhone >> >> -- >> >> -- Diese Nachricht wurde von meinem Android-Gerät mit K-9 Mail gesendet.
Re: Rolm Computers: 1602, 1602A, 1602B, 1666, MSExx (was Data General Nova Star Trek)
Hi Tom, thanks for getting in touch. I got some hardware and documentation from PWA as they wanted to get rid of all the small portion which remained. I focused on the 16 bit machines so I have 1602 (forwarded 1602b to a colleague) and a mse14. All restored to working condition. With two colleagues we built a hdd simulator, so the mse is running mapped RDOS. My marvels I guess are a microcode development kit for the 1602 and the Rolm "mother". Currently I am in Denver to attend the nova-at-50.org... More if interested next week... Erik. Am 20. Oktober 2018 17:03:22 GMT-06:00 schrieb Thomas Hollowell via cctech : >Hi Eric, >My name is Tom Hollowell. I took the US support of Rolm in 1998. PWA >assumed the international. I noticed that you have some ROLM hardware. >I may be interested in finding out what you have. >Let me know, >Thanks, >Tom > >Sent from my iPhone -- Diese Nachricht wurde von meinem Android-Gerät mit K-9 Mail gesendet.
Re: Rolm Computers: 1602, 1602A, 1602B, 1666, MSExx (was Data General Nova Star Trek)
Hi Paul, thanks for your reply - good to see that there are still guys out there who worked with this heavy iron. So you have been in the UK while working with the Rolm? I guess it was a 1602B or later and pesumably some airborne early warning stuff? Best wishes, Erik. Am 21. Oktober 2018 03:12:52 GMT-06:00 schrieb Paul Anderson via cctalk : >I was at the DG factory school at Southbourgh in 76 or 77, and worked >on a >ROLM NOVA while at RAF Chicksands in the late 70s. Unfortunately, my EX >through out all of the manuals, prints, etc along with a complete set >of >SAGE (ANFSQ-7) docs. > >Paul > >On Sun, Oct 21, 2018 at 3:38 AM Thomas Hollowell via cctalk < >cctalk@classiccmp.org> wrote: > >> Hi Eric, >> My name is Tom Hollowell. I took the US support of Rolm in 1998. PWA >> assumed the international. I noticed that you have some ROLM >hardware. I >> may be interested in finding out what you have. >> Let me know, >> Thanks, >> Tom >> >> Sent from my iPhone -- Diese Nachricht wurde von meinem Android-Gerät mit K-9 Mail gesendet.
Edinburgh Computer History - Silverknowes machines...
Hi there, is probably Ken Adam on this list? He was in various roles working at Ferranti/Edinburgh probably during the 1970ties and 1980ties and I'd like to get in touch because of his 2013 posting in a yahoo group... https://groups.yahoo.com/neo/groups/EDINBURGH-COMPUTER-HISTORY/conversations/messages/342 ...relating to early computers made in Silverknowes for inertial navigation systemas? I tried posting in the EDINBURGH-COMPUTER-HISTORY group of course. It would be great if any more information on this stuff survived ;-) Any hints are welcome, happy computing, Erik.
Re: Wanted: Parsytec SCSI-T or BBK-S4.
Hi Andrew, thanks for your email and great to hear, that you managed to get hands on a BBK-S4! On Sun, 1 Oct 2017, Andrew Back wrote: Have you got PARIX up and running with the Power Xplorer? Yes, 1.3.something. I even ported the povray to this hardware using an older pvmpov version. Most of the time I use some single Trapu boards from a MegaFrame... Does it support the PPCs? Yes, for Transputer-only I am using Helios on the PowerXplorer (PPCs idle in this case) and with PARIX, the Transputers are doing the networking part whereas the PPCs execute the user code. What do you have got running on your Transputer machines? I still haven't got round to restoring them. They were stored in a damp cellar and would benefit from dismantling and a thorough overhaul. OK, so I am crossinf my fingers, that you will find some time in the future and the S4 within your IPX is a good point to start at! Well, I managed to get an SBus card, although there are no stickers on the EPROMs and so I hope it will work. In an emergency I can supply images of the EPROMS I guess. The first test is restoring the IPX and if your BBK-S4 can be accessed you are a good step further. My first test here alway is to issue a... /usr/etc/transp/s4diag ...to get a dump and see in which slot the BBK-S4 acutally is. In my case: slot 0 - NO VALID SBUS DEVICESBus slot 1 - NO VALID SBUS DEVICESBus slot 2 - NO VALID SBUS DEVICESBus slot 3 - 'CWA: BBKS4' No link available for checking versio in a Sparcstation IPX to use with it. I need to spend about ??450 on Lemo connectors to make cables for it! Well, one cable will be enough to start with. I am normally using ony one entry into my PowerXplorer-setup. My biggest test run was with a mesh of 8 Trapus/PPCs. I also picked up a small Parsys system, but it sadly only has a single T9000 HTRAM. Can't seem to find any documentation on it either. Well, I guess, these are very rare and although I have got a preview chip (i.e. really only the chip without housing, pins etc.), I also have never seen any documentation or even software for the T9000... Best regards and good luck, Erik.
Re: SPARCstation 20 and dual CPUs
On Fri, 4 Aug 2017, John P. Willis via cctalk wrote: Does anyone know if there is some physical jumper or OpenBoot parameter required in order to enable multiprocessor support on a SPARCstation 20? I do not know of such a switch/jumper. Both my SS2 I upgraded to 2-CPU and 2*2 CPU did not require some change to the NVRAM settings or changing a jumper. But there was a FirwarePROM with the CPU-Sets (HyperSPARC). Probably you should try moving not only the CPU but also the EPROM with firmware to check this... Best regards from Germany, Erik.
