November 2025 - cctalk - classiccmp.org

Seagate half high hard drive face plate & cables

by Mike Katz

Does anyone out there have a spare 1/2 high 5 1/4" Seagate MFM hard drive face plate (ST-221, ST-251, etc.) that they can let go cheap? And also a 34 conductor dual drive cable and a single 20 on single drive cable? Thank you. Contact me off list at bitwiz(a)12bitsbest.com

8 months, 1 week

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Various vintage computers and peripherals for sale

by martin .

As we're emigrating soon, I am starting so find a new home for my collection of vintage computers and peripherals. On offer today is: Dec PDP 8E* ==========on a standA list of modules included in the link below. including with the machine comes: - Rail mounting hardware - Spare power supply - A long flat cable - Bootstrap card M847E - 32k SRAM + Bootstrap card from Vincent Slyngstad (new kit, unassembled) ASR33 Teletype* ==============on its original stand Hazeltine H2000 terminal* ========================in pristine condition on a stand Hazeltine H2000 terminal========================probably not working (got somehow damaged during transport from last seller to me, and I never got around checking out what's wrong) Tektronix 4014-1* Graphics Terminal ===================================on its original stand Please make an offer for either some or for all of the items (to martin(a)meiner.ch). *) Items marked with a star were functioning well a few years ago when I was actively acquiring them. As times went by, it could be that one or the other may need TLC. I have not tested them again for full functionality. Items are located near Zurich/Switzerland. It is the buyer's responsibility to either pick the items up or to arrange packing and shipping by a forwarder. Here a link to cloud storage showing photos and other information of the units: http://e.pc.cd/o3sy6alK More equipment to follow in a few weeks / months (will rather be elder calculators).

8 months, 1 week

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Replacements for DEC 3639

by Christian Corti

It seems that nowadays you can't get *any* replacement for failing DEC 3639 aka 2N3639 transistors. All parts are obsolete and unobtanium, e.g. 2N3640, PN3640, MMBT3640 and so on. So, what can be used instead? The most important electrical parameter is the storage time. It needs to be *very* low, around 20-30 ns. Does it mean that a failing PDP-8 will stay a dead PDP-8 from now on? Christian

8 months, 1 week

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ST-251 MFM Hard Drive sector size question

by Mike Katz

I have an ST-251 42MB MFM hard disk drive. The documentation says the drive is 512 bytes per sector. I don't know if this is fixed (hard sectored) or not. My problem is my operating system (OS/9 Level II) wants 256 bytes per sector. The OMTI 20C-1 controller can handle that but I'm not sure if the ST-251 can. Does anyone know if the ST-251 can support 256 bytes per sector and/or how to configure it for 256 bytes per sector? Thank you, Mike

8 months, 2 weeks

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Ancient versions of the VAX Workstation Software (VWS)

by Hans-Ulrich Hölscher

I'm looking for ancient versions of the VAX Workstation Software (VWS) for my software collection and for my VAXstation I: - V1.0 - V1.1 - V2.0 - V3.0 V1.0 (which was called "uVMS VAXstation I graphics/windowing softwarere" back then) and V1.1 are the most wanted ones, because they are the only ones that run on MicroVMS V4.0 for the VAXstation I. Version 1.0 was shipped on two RX50s, labeled “VSI010 1/2” and “VSI010 2/2”; later versions grew bigger and from V2.0 onwards TK50s were used besides RX50 floppies as well. Best Regards, Ulli

8 months, 2 weeks

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Apple ADB Mouse

by Cameron Kelly

Hello, I am wondering if anyone here would be willing to part with their Apple ADB Mouse and is located within Canada? Best Regards, Cameron

8 months, 2 weeks

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80386 - 1985

by Murray McCullough

40 years ago this year Intel came out with the 80386 – 386 – or i386. Either seems to be correct. What this meant was a memory address of 4GB, far beyond what an average computer user would need or want, but was so much more than previously(8086, 80286); ‘true’ multi-tasking which for the average computer user didn’t mean all that much; and paging, which made virtualization possible- experimenters were over-joyed! What all this contributed to was the end of the classical/vintage-computing era. Whether this began the time of open-source OS development is debatable! Happy computing? Murray 🙂

8 months, 2 weeks

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Unix V4

by Paul Koning

https://discuss.systems/@ricci/115504720054699983 and https://www.theregister.com/2025/11/07/unix_fourth_edition_tape_rediscovere… Amazing. paul

8 months, 2 weeks

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what is it? 3850 stuff

by Donald Whittemore

Got this on eBay. 7 3850 cartridges, a piece of mag tape and some metal device in a nice box. I am trying to determine what the metal thing is. Some kind of alignment tool? For cartridge insertion in MSS unit, not track alignment? https://www.myimagecollection.com/whatisit/pic1.jpg https://www.myimagecollection.com/whatisit/pic2.jpg

8 months, 3 weeks

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OS chart

by Paul Koning

Via one of the articles about that Unix V4 tape I found this https://eylenburg.github.io/os_familytree.htm which is quite an impressive chart of operating systems old and new. A few bits are clearly incorrect or missing; for example, P/OS and TRAX are both not there. I was going to mention them to the author of that chart but I don't actually know the correct placement. (Is P/OS an RSX-11/M or M+ derivative? I should know but don't.) Neat to see RSX-15 mentioned as the ancestor of RSX-11/D. Did the earlier RSX-11 versions ever ship? I know I have seen traces of /A and/or /C... The DOS-11 and RSTS entries aren't quite right either, I can send feedback for those. Also, while VMS is reasonably listed as RSX-11/M derivative, I always thought that VAXElan was unrelated. Along the same lines, where would MicroPower/Pascal fit? paul

8 months, 3 weeks

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cctalk November 2025