test-drb

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101090 discussions

by jnc＠mercury.lcs.mit.edu

> From: Swift Griggs > I see a lot of traffic about them on the list and I went out to > discover "why so cool?" One word - 'crunch'. The 6600 especially, but also its successors (7600, etc) were _the_ number-crunching monsters of their day. For everyone who had a scientific/engineering application that needed lots of cycles - especially floating-point - that was _the_ machine to have. IBM tried to outdo them, but spent a fortune, and didn't really get there - the 360/9x was essentially a failure - only 15 /91's and 2 /95's were ever built. (And IBM was later sued for predatory sales practices for announcing them before they knew they could make them.) IBM just couldn't match Seymour Cray. Speaking of whom, the 6600 was the source of the famous Watson memory (and Cray's sarcastic response) - Google it! Noel

10 years, 1 month

Still ISO: Infotek MX-30 Memory boards for Infotek FP-30 (HP 9830 upgrade)

by derschjo＠gmail.com

Hey all -- Several years ago (well, three years ago, anyway) I stumbled upon a beat-up, incomplete HP 9830 desktop computer/calculator that had been upgraded with an Infotek FP-30 CPU upgrade. Unfortunately, it's missing the special memory boards (the MX-30) the system requires. I asked around back then and had no luck, I figured I'd try again. If anyone has any parts for this rare beast, drop me a line. Alternately, if someone else has a need for the parts I do have, let me know and maybe we can work something out. It would be nice to get a working system (even if it's not mine) out of this stuff. Thanks! Josh

10 years, 1 month

CDC 6600 - Why so awesome?

by jnc＠mercury.lcs.mit.edu

> the 6600 was the source of the famous Watson memory Oops, typo; 'memo'. Noel

10 years, 1 month

Found cleaning out stuff from before gray hairs and needing glasses

by pete＠petelancashire.com

http://petelancashire.com/gallery/main.php?g2_itemId=7139

10 years, 1 month

old friend is slimming down the warehouse

by sales＠elecplus.com

An old friend of mine in GA is slimming down his warehouse. I know a long time ago people sent me some pics and lists of things wanted, but that was a long time ago. If you are looking for old servers, big blue IBM things, DEC stuff, etc., please take a few minutes to send the following info to oldthingswantednow at gmail.com The name of the item A short description A link to a pic, or attach a pic What you want to pay for it The expected condition (tested, old and dirty is fine, etc.) His health is not the best, but he wants this stuff to go to people who will appreciate it, rather than by the pound. He will do his best to answer everyone. Inventory ranges from old typewriters to mainframes, and everything in between. Cindy Croxton Electronics Plus

10 years, 1 month

HP Series-80 computers - PRM-85 board case? ... maybe!

by ball.of.john＠gmail.com

>Anyone with a 3d printer want to make one for us? > >J Not only do I also own a PRM-85 but I do have part-time access to a 3D printer. If I can get the prototyped models (and the model itself fits within the limits of the printer bed)I can verify that they fit together in an HP 80 series machine (85 in my case)and that the board itself fits inside the enclosure however due to membership restrictions at our local makerspace I cannot use the printer to fulfill any orders, plus they will eat up a lot of filament. -John

10 years, 1 month

Monitor refresh rate query

by jnc＠mercury.lcs.mit.edu

> From: Chuck Guzis > It's not the refresh rate that will kill things, but the horizontal > frequency. The high voltage in most CRT monitors (and TVs) is developed > from the scanning signal via a high-voltage "flyboack" transformer > ... > Ultimately, if taken too far, the voltage in the FBT secondary exceeds > the ratings of the winding insulation; an arc develops between windings > and the FBT self-destructs So, with Chuck's explanation (above) in hand, eventually my brain turned on, and I was able to work out what the deal is, and whether my monitor is safe; it also explains the somewhat contradictory CRT monitor manual: HP M50 manual says "Setting the screen resolution/refresh rate combination higher than 1024x768 at 60 Hz can damage the display." Even though the same document lists the vertical frequency range as "50-100 Hz"! They mention both the resolution and "refresh rate" since those two together control the horizontal flyback frequency, which Chuck pointed out as the key. (Well, the line count - 768 - is involved there, not the line length in pixels - although the latter will influence the maximum video bandwith or "dot rate" that needs to be supported - 65 MHz for this particular monitor.) The horizontal retrace frequency is simply the vertical retrace frequency, times the number of scan lines per vertical retrace plus a small slop factor for the actual retrace duration. So my monitor was running 1024x768 - but interlaced, so only 364 lines per screen scan (alternating odd and even lines in successive scans). I was seeing a refresh frequency of 44 Hz - but for full scan of all lines; the actual vertical retrace is being produced at 87 Hz. So the horizontal retrace frequency is about 87 * 364 = ~32 KHz - well within what the monitor can handle (30-49 Khz for the horizontal retrace, per the spec). So the monitor is safe! Probably by the time this monitor came out, the interlaced XGA format had fallen into disuse, and so they didn't need to clarify that "resolution/refresh rate combination higher than 1024x768 at 60 Hz can damage the display" refers to 'progressive' displays, not interlaced. And of course, as previously pointed out, the interlace explains why no LCD displays will work. So I'll have to carefully hoard my remaining video monitors! ;-) Thanks to everyone who helped me work this out... Noel

10 years, 1 month

Programming for the Alto's Mesa

by lproven＠gmail.com

>From the discussions around Y Combinator's Alto restoration... (Some may not know that the founder of Y Combinator is Paul Graham, using some of the money Yahoo! paid him for Viaweb, which became Yahoo Stores. PG is a Lisp champion and evangelist.) The Alto restoration is being discussed on Hacker News, Y Combinator's very successful forums: https://news.ycombinator.com/item?id=11929396 This comment struck me: ? Animats 2 days ago I just looked in some boxes I haven't opened in decades. I have "Mesa Language Manual, Version 5.0, April 1979". If the people with the Alto need this, let me know. If the world had used Mesa instead of C, computing would have been far less buggy. Mesa was a hard-compiled language, but it had concurrency, monitors, co-routines ("ports", similar to Go channels), strong type safety, and a sane way to pass arrays around. In the 1970s. (I should donate this stuff to the Computer Museum. I just found the original DEC Small Computer Manual, many 1960s UNIVAC mainframe manuals, and a reel of UNIVAC I steel magnetic tape.) ? I knew that the original Smalltalk boxes weren't Smalltalk all the way down to the metal, and that there was an OS and language, Mesa, underneath... but I didn't know it was used for anything much *else* or that some considered it important. Anyone here know or remember Mesa? I'd like to hear more about it. -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

10 years, 1 month

Sun4 370 PSU Maintenance/Schematics

by aswood＠t-online.de

Hello all, I do have an Symbolics UX1200 plugged into a Sun4 370 host. Before powering the host, just to be secure, I'd like to check the psu - or if the psu will be broken, I'd like to try to fix it. Yesterday I'd a look into the psu - very complicated layout! Is there any known documentation, servicing and maintenance documentation or schematics for psus used in Sun server/workstation available, of course esp. for psus used in Sun4 370 systems? -- Andreas ?

10 years, 1 month

Programming for the Alto's Mesa

by jnc＠mercury.lcs.mit.edu

> From: Josh Dersch >> ISTR that BravoX was written in Mesa. -- Ian > Yes it was, as was MazeWar ?? There was a MazeWar on the Alto, early on, and I'm not sure that version was in Mesa. Maybe someone re-implemned it in Mesa for some of the later machines? (Of course, all the Xerox ones were inspired by the much earlier Imlac one.) Noel

10 years, 1 month

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