core matt repair

Send cctech mailing list submissions to cctech at classiccmp.org To subscribe or unsubscribe via the World Wide Web, visit http://www.classiccmp.org/mailman/listinfo/cctech or, via email, send a message with subject or body 'help' to cctech-request at classiccmp.org You can reach the person managing the list at cctech-owner at classiccmp.org When replying, please edit your Subject line so it is more specific than "Re: Contents of cctech digest..." Today's Topics: 1. Re: DEC PDP-8/e H212 core mat repair (steven at malikoff.com) 2. Re: DEC PDP-8/e H212 core mat repair (Joshua Rice) 3. Re: DEC PDP-8/e H212 core mat repair (Joshua Rice) 4. Re: DEC PDP-8/e H212 core mat repair (Tom Hunter) 5. Re: DEC PDP-8/e H212 core mat repair (Jules Richardson) 6. Re: DEC PDP-8/e H212 core mat repair (Rod Smallwood) 7. Tektronix 8002 microprocessor lab software (Jules Richardson) 8. Re: Tektronix 8002 microprocessor lab software (Zane Healy) 9. Re: Tektronix 8002 microprocessor lab software (Al Kossow) 10. Re: Tektronix 8002 microprocessor lab software (Al Kossow) 11. Re: Tektronix 8002 microprocessor lab software (Al Kossow) 12. Re: Tektronix 8002 microprocessor lab software (Jules Richardson) 13. Re: Tektronix 8002 microprocessor lab software (Jules Richardson) 14. Re: Tektronix 8002 microprocessor lab software (Zane Healy) 15. Re: Items Wanted (Jay Jaeger) 16. Re: Items Wanted (Zane Healy) 17. Re: DEC PDP-8/e H212 core mat repair (Toby Thain) ---------------------------------------------------------------------- Message: 1 Date: Mon, 19 Jul 2021 17:59:59 +1000 From: steven at malikoff.com To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: DEC PDP-8/e H212 core mat repair Message-ID: <84f709701f774aebb1a07a8bbb6eb091.squirrel at webmail04.register.com> Content-Type: text/plain;charset=utf-8 Tom said I have no idea how DEC made theirs but for IBM's System 360, one of their engineers came up with the clever idea of stretching the core wire so it necked and broke, leaving a work-hardened tapered point to thread the cores with. They patented it https://patents.google.com/patent/US3314131A (Source: page 187 of 'IBM's 360 and early 370 Systems' by Pugh et al) On a Youtube film about the 360 they show cores being vibrated into the correct orientation on a jig board. ------------------------------ Message: 2 Date: Mon, 19 Jul 2021 09:40:44 +0100 (BST) From: Joshua Rice <rice43 at btinternet.com> To: CCtalk <cctalk at classiccmp.org> Subject: Re: DEC PDP-8/e H212 core mat repair Message-ID: <55e9b1e8.2735f.17abdecb557.Webtop.91 at btinternet.com> Content-Type: text/plain; charset=UTF-8; format=flowed ------ Original Message ------ From: "Tom Hunter via cctalk" <cctalk at classiccmp.org> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Sent: Monday, 19 Jul, 2021 At 06:33 Subject: DEC PDP-8/e H212 core mat repair I am curious if anyone has attempted to repair (replace) a broken wire in a PDP-8/e H212 (MM8EJ) core mat (8 k word). The cores are not visible without a microscope. I cannot imagine how these were even manufactured and wonder if DEC service centers repaired core mat faults or if faulty boards were simply discarded. CDC 6600 cores were huge in comparison and I would not hesitate to replace a broken core wire on those. Best regards Tom Hunter I believe much of the core manufacturing for DEC minicomputers was outsourced, but a lot of it had become much more automated by the late 60's and early 70's. I believe it was done by machine, with a tray to hold the toroids in place, and a very fine needle-like "bobbin" that threaded the wires through the toroids. I believe threading the cores by hand had become largely obsolete by the time the PDP-8 came onto the market. Though i can't confirm it, i highly doubt that DEC engineers would repair core planes. These would more likely be sent back to the manufacturer for "recycling", with the cores being recovered and reused. It's worth noting that most computer manufacturers appreciated the fragility of core memory planes at the time, with most of them being protected with either PCB's or perspex/plastic shields on top of the core planes. In this way, it was rather difficult for a clumsy ol' technician to put his thumb through the planes as he was servicing machines. Josh ------------------------------ Message: 3 Date: Mon, 19 Jul 2021 09:52:13 +0100 (BST) From: Joshua Rice <rice43 at btinternet.com> To: CCtalk <cctalk at classiccmp.org> Subject: Re: DEC PDP-8/e H212 core mat repair Message-ID: <5d5f0788.273f3.17abdf7399b.Webtop.91 at btinternet.com> Content-Type: text/plain; charset=UTF-8; format=flowed ------ Original Message ------ From: "Tom Hunter via cctalk" <cctalk at classiccmp.org> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Sent: Monday, 19 Jul, 2021 At 06:33 Subject: DEC PDP-8/e H212 core mat repair I am curious if anyone has attempted to repair (replace) a broken wire in a PDP-8/e H212 (MM8EJ) core mat (8 k word). The cores are not visible without a microscope. I cannot imagine how these were even manufactured and wonder if DEC service centers repaired core mat faults or if faulty boards were simply discarded. CDC 6600 cores were huge in comparison and I would not hesitate to replace a broken core wire on those. Best regards Tom Hunter These patents might be enlightening. I'm sure there's others, but these are some i've found on a quick search. https://patents.google.com/patent/US4161037A <https://patents.google.com/patent/US4161037A> https://patents.google.com/patent/US3668664 <https://patents.google.com/patent/US3668664> Josh ------------------------------ Message: 4 Date: Mon, 19 Jul 2021 19:02:25 +0800 From: Tom Hunter <ccth6600 at gmail.com> To: Joshua Rice <rice43 at btinternet.com>, "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: DEC PDP-8/e H212 core mat repair Message-ID: <CAALEduCP_GLHuuMG2UO3CU329-_3E=RPqzVZ+RUGC6gTVQNFow at mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Thanks Josh, I read through both patents but struggled to fully understand what they described. Unfortunately patents are written in broad terms to cover as much as possible. It was very interesting nevertheless. Best regards Tom Hunter On Mon, Jul 19, 2021 at 4:52 PM Joshua Rice via cctalk < cctalk at classiccmp.org> wrote: ------------------------------ Message: 5 Date: Mon, 19 Jul 2021 16:50:10 -0500 From: Jules Richardson <jules.richardson99 at gmail.com> To: cctalk at classiccmp.org Subject: Re: DEC PDP-8/e H212 core mat repair Message-ID: <769e6168-9024-fa20-5b9c-ed1cb91ec641 at gmail.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed On 7/19/21 3:40 AM, Joshua Rice via cctalk wrote: I've got a trio of planes here, two of which are from a Lockheed MAC-16, but the other one is made by Keronix out of Santa Monica for an unknown machine (dated 1973, model number "P4" and p/n 816335 if that means anything to anyone, approx 16"x16" with two 100-pin, double-sided finger edge connectors on 0.1" spacing). Anyhoo, the Keronix one has a sticker on it saying it was repaired by DMA, inc. in Amery, WI in 1980 - which might suggest that there were third parties around working on boards, rather than them having to go back to the manufacturer for repair. (I have no idea what the nature of the repair was, of course; maybe it was to surrounding logic rather than the mat itself). Yes, that's how all the ones I've ever seen have been. The Keronix one has an additional shield over the top of the entire PCB, on top of the one protecting the cores. Jules ------------------------------ Message: 6 Date: Mon, 19 Jul 2021 23:06:26 +0100 From: Rod Smallwood <rodsmallwood52 at btinternet.com> To: Jules Richardson via cctalk <cctalk at classiccmp.org> Subject: Re: DEC PDP-8/e H212 core mat repair Message-ID: <d5251315-3f4c-3a46-e36e-71949a90c26e at btinternet.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed Yes most core stringing was outsourced. By hand under magnification was used. I cant recall any references to automation. That would br down to the supplier. The story I heard was at least some were done by embroidery girls in Hong Kong Rod Smallwood ? -- Digital Equipment Corporation? 1975 to 1985 On 19/07/2021 22:50, Jules Richardson via cctalk wrote: ------------------------------ Message: 7 Date: Mon, 19 Jul 2021 18:03:46 -0500 From: Jules Richardson <jules.richardson99 at gmail.com> To: CCtalk <cctalk at classiccmp.org> Subject: Tektronix 8002 microprocessor lab software Message-ID: <5b8f634d-93c9-22c2-fd05-6e1937767883 at gmail.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed Just out of interest, is the software for the Tektronix 8002 microprocessor lab archived out there anywhere? What I believe is one popped up on one of my Facebook groups, and it'd be a trek to get it even if I can arrange a good price with the current owner - but it sounds like the software at the site, if it still exists, is unlikely to surface from a huge pile of detritus, so that automatically puts things right in boat anchor territory. There may or may not be a terminal, too; I get the impression those were optional (I've been told that there are two Tek terminals, I just don't know if they're the right models for this system). cheers Jules ------------------------------ Message: 8 Date: Mon, 19 Jul 2021 16:11:32 -0700 From: Zane Healy <healyzh at avanthar.com> To: Jules Richardson <jules.richardson99 at gmail.com>, "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: Tektronix 8002 microprocessor lab software Message-ID: <ED3B17DB-6591-493A-B470-D940A5E18A91 at avanthar.com> Content-Type: text/plain; charset=utf-8 You might check with the Tektronix museum, and see what they know. As far as I know, they aren?t actually part of Tektronix. Zane ------------------------------ Message: 9 Date: Mon, 19 Jul 2021 16:15:11 -0700 From: Al Kossow <aek at bitsavers.org> To: Jules Richardson via cctalk <cctalk at classiccmp.org> Subject: Re: Tektronix 8002 microprocessor lab software Message-ID: <395e3439-3632-33ea-9579-883ad602b8e5 at bitsavers.org> Content-Type: text/plain; charset=iso-8859-15; format=flowed On 7/19/21 4:03 PM, Jules Richardson via cctalk wrote: I have some but it is hard-sectored so I've never tried to read it. It's pretty unlikely anyone at the tek museum would have tried to recover the floppies even if they had them. One of my 'really like to try to recover' things at CHM is we have a bunch of floppies from the company that designed it for Tek, but someone put a center punch through every disk, so I'm going to have to take them out of the jacket and try to flatten the dent out as best as I can. ------------------------------ Message: 10 Date: Mon, 19 Jul 2021 16:20:19 -0700 From: Al Kossow <aek at bitsavers.org> To: cctalk at classiccmp.org Subject: Re: Tektronix 8002 microprocessor lab software Message-ID: <a0c2c3a7-4c74-81da-1f40-a581d3f29fda at bitsavers.org> Content-Type: text/plain; charset=iso-8859-15; format=flowed On 7/19/21 4:03 PM, Jules Richardson via cctalk wrote: > It would be nice to save a complete system though, since most have been tossed out since there is little practical use for them now. I never had a whole one, just board sets for various processors that I collected over the years. ------------------------------ Message: 11 Date: Mon, 19 Jul 2021 16:25:21 -0700 From: Al Kossow <aek at bitsavers.org> To: Al Kossow via cctalk <cctalk at classiccmp.org> Subject: Re: Tektronix 8002 microprocessor lab software Message-ID: <f4bafaa8-f4d9-95aa-016e-68d36d7c8b8a at bitsavers.org> Content-Type: text/plain; charset=iso-8859-15; format=flowed On 7/19/21 4:20 PM, Al Kossow via cctalk wrote: I've collected a LOT of in-circuit emulators and microprocessor development systems over the decades, and I'm trying to decide right now what I'm going to do with them. ------------------------------ Message: 12 Date: Mon, 19 Jul 2021 19:53:25 -0500 From: Jules Richardson <jules.richardson99 at gmail.com> To: cctalk at classiccmp.org Subject: Re: Tektronix 8002 microprocessor lab software Message-ID: <8d864579-a8be-c8b1-9734-d208d0c10bcf at gmail.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed On 7/19/21 6:20 PM, Al Kossow via cctalk wrote: >> >> Just out of interest, is the software for the Tektronix 8002 >> microprocessor lab archived out there anywhere? >> > > It would be nice to save a complete system though, since most have > been > tossed out since there is little > practical use for them now. Well sadly it's looking like game over. By the sounds of it there's a basement full of old equipment and boards, and a scrapper out in OH has offered $6k for the lot, sight unseen, just on the hope that they can make a buck on the gold and palladium content. The next offer seems to be from someone who's planning on just dumping it on ebay - so if the scrapper deal falls through maybe it'll resurface on That Auction Site for lolprice... This is starting to feel like one of those situations where it's a huge shame that the original owner of this stuff didn't have a will expressing what should be done with it all. ------------------------------ Message: 13 Date: Mon, 19 Jul 2021 20:17:27 -0500 From: Jules Richardson <jules.richardson99 at gmail.com> To: cctalk at classiccmp.org Subject: Re: Tektronix 8002 microprocessor lab software Message-ID: <a734724d-b7f5-deb8-6e1f-10e429e8f43f at gmail.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed On 7/19/21 7:53 PM, Jules Richardson via cctalk wrote: annnnd... right after I hit send on that, things start looking up again. The guy responsible for this stuff doesn't seem to want it to get scrapped any more than I do, and he got in touch with folks down at Cape Canaveral (there are various ex-NASA things in the pile), then talked to the family of the estate; it sounds like some of it at least might get donated to the collection down there. I'm not sure about non-NASA things at this point, we'll see - but it sounds like there's interest now in not junking it, at least! Jules ------------------------------ Message: 14 Date: Mon, 19 Jul 2021 19:56:29 -0700 From: Zane Healy <healyzh at avanthar.com> To: Jules Richardson <jules.richardson99 at gmail.com>, "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: Tektronix 8002 microprocessor lab software Message-ID: <DE9B0230-1D5D-4416-992D-6B60A7886F17 at avanthar.com> Content-Type: text/plain; charset=utf-8 On Jul 19, 2021, at 6:17 PM, Jules Richardson via cctalk <cctalk at classiccmp.org> wrote: That?s a bit of good news! Zane ------------------------------ Message: 15 Date: Mon, 19 Jul 2021 22:03:49 -0500 From: Jay Jaeger <cube1 at charter.net> To: cctalk at classiccmp.org Cc: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: Items Wanted Message-ID: <9ac110f9-2407-c9ba-6ec5-d70e9fd10d26 at charter.net> Content-Type: text/plain; charset=utf-8; format=flowed On 7/11/2021 9:33 AM, Eric Moore via cctalk wrote: You and me both. ;) I have one - and I intend to keep it. Do you mean a device that emulates a SCSI drive with an SD card? Why not just go out and purchase a SCSI2SD V5.1 - a little slower than the newer ones, but works fine in my Sun, SGI and Intergraph Boxen. I also just bought one of the less expensive Androda SCSI emulators - designed for Macs, really, but it might work and it is relatively inexpensive. FYI, if you have "Pizza Boxes" then I have found that the cable commonly available (VGA one end, 13W3 on the other - the one with switches on it) works well on both Sun and SGI Boxen. Google Sun VGA 13W3 on eBay. You probably want the one with the switches.) I have some old Pertec formatters that have no bus interface. Free to good homes. Some were mouse houses for a while, but were subsequently cleaned up reasonably well. Models F649-72 (2 of those) and F649-40. Heavy to ship. In addition, I think I have a TC031, Pertec/QBus (I think) that I really am not using. I tried it out once - I think the issue was that I had a Pertec interface speed mismatch between it and the HP drive I have with a Pertec interface (which also has issues with loading tape.) I suspect it is formatted, however. I have a Fabritek memory box. I think it was on a PDP-12, but am not 100% certain without going back and looking at old paperwork. I am not sure of its condition, electrically speaking - whether it had slots for cables, or cables coming out of it, and if the latter, whether they are intact. It has been stored in my basement for decades, low and dray. That would take some work to pry out of my hands. I am not aware of any such beasties in the wild. MFM, yes, but I haven't seen ESDI. I would love for such a thing to exist, thinking of my Apollo, 3B2 and IBM RT/PC workstations. ------------------------------ Message: 16 Date: Mon, 19 Jul 2021 21:00:27 -0700 From: Zane Healy <healyzh at avanthar.com> To: Jay Jaeger <cube1 at charter.net>, "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: Items Wanted Message-ID: <3EFC578F-97F0-468A-B3F1-8E4C17094843 at avanthar.com> Content-Type: text/plain; charset=utf-8 On Jul 19, 2021, at 8:03 PM, Jay Jaeger via cctalk <cctalk at classiccmp.org> wrote: Yeah, they are sort of a necessity. The SCSI2SD v5.1 should be faster than the Q-Bus. I bought several recently, and plan to put one in my PDP-11/73. I even opted for these for my VAXstation 4000?s. I figure I?ll use the newer ones in an AlphaStation. I?d also love to have one of these, preferably using SD or CF cards. The Webster WQESD/04 card is a fantastic card, it?s only downfall is that it works with ESDI drives, rather than SCSI, and they?re big and loud. :-) Zane ------------------------------ Message: 17 Date: Mon, 19 Jul 2021 18:16:28 -0400 From: Toby Thain <toby at telegraphics.com.au> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: DEC PDP-8/e H212 core mat repair Message-ID: <820d43ed-e32d-4394-4038-bb662f5e6798 at telegraphics.com.au> Content-Type: text/plain; charset=iso-8859-15 On 2021-07-19 6:06 p.m., Rod Smallwood via cctalk wrote: There's more detail on early core production in the book "IBM's Early Computers", iirc. (And possibly "A Few Good Men From Univac".) End of cctech Digest, Vol 82, Issue 15 **************************************