- vcf-midatlantic - lists.vcfed.org

Re: [vcf-midatlantic] UPDATE -- Festivus food thread: Who'sbringingwhat?
by VAXman＠tmesis.org 03 Dec '15

03 Dec '15

Bill Dromgoole via vcf-midatlantic writes: >On Nov 25, 2015, at 4:40 PM, Chris via vcf-midatlantic wrote: > >> Also there are three cases of fanfold pin feed paper up for grabs if >VCF > doesn't want it. > >What size?= > >9 1/2 by 11 inches Plain? I wouldn't mind having some.

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8 inch PT DOS disks
by Kelly Leavitt 03 Dec '15

03 Dec '15

Did anyone come get these from me? If not, I'd like to dig them up tonight or tomorrow and bring them to Festivus if anyone can use them. corey986 expressed an interest but I don't recall anyone coming for them. This was in November of 2013. Kelly Here is the post from Corey RE: PT DOS on 8" free Nov 24, 2013 Actually Kelly, email me at corey986@...I can swing up to you this week and pick them up. I think your in northern NJ up near the NY border?There aren't too many working Helios that can use those disks. I know I'd put them to good use.I actually recently setup one of my Sol-20 to be my main telnet/SSH machine for work because I love the keyboard so much. Sure there is a raspberry pi involved ;-)Cheers, Corey

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Virtual 3D Presentation of the Living Computer Museum
by Christian Liendo 03 Dec '15

03 Dec '15

I figured you guys would like this. https://my.matterport.com/show/?m=FSBUxKALmPW

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Re: [vcf-midatlantic] Core Memory Purchase
by John Sully 03 Dec '15

03 Dec '15

Thanks for your help everyone. This is one of the stacks I was looking at: http://www.ebay.com/itm/USSR-Russian-Magnetic-Ferrite-Core-Memory-CUBE-from… I'm planning to build my own drive electronics so the less electronics on it the better in my opinion. Another goal is to have it big enough to "be interesting". Eventually I want to integrate it into a TTL CPU I'm planning to build. For now though I'd just be happy controlling it with a microcontroller.

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Re: [vcf-midatlantic] Core Memory Purchase
by Jonathan Gevaryahu 03 Dec '15

03 Dec '15

Here is a response about reviving old core memory boards, from Kevin 'kevtris' Horton, who has revived 3 of them in the past. -------- Forwarded Message -------- Subject: Re: Fwd: [vcf-midatlantic] Core Memory Purchase Date: Thu, 3 Dec 2015 01:15:52 -0500 From: K Horton <kevtris(a)comcast.net> To: Jonathan Gevaryahu <jgevaryahu(a)gmail.com> On 12/2/2015 22:17 , Jonathan Gevaryahu wrote: > kevtris, you have some experience resurrecting core memory. Do you > want to respond here? > > > -------- Forwarded Message -------- > Subject: [vcf-midatlantic] Core Memory Purchase > Date: Wed, 2 Dec 2015 16:56:35 -0800 > From: John Sully via vcf-midatlantic > <vcf-midatlantic(a)lists.vintagecomputerfederation.org> > Reply-To: vcf-midatlantic > <vcf-midatlantic(a)lists.vintagecomputerfederation.org> > To: vcf-midatlantic(a)lists.vintagecomputerfederation.org > CC: John Sully <john(a)csquare.ca> > > > > I'm planning to resurrect some old core memory as a hobby project. I was > wondering if anyone with experience on getting this memory working could > provide some insights on what I should look for. > > EBay seems to have a large number of expensive ones that don't appear to be > in working order - along with some much cheaper (relatively speaking) > russian made stacks. > yes, this is a big problem. if the core memory is shown "open" on ebay, don't buy it. there's a 99% chance it's going to be broken. The cores and wiring are extremely fragile, just blowing on it can destroy it (well not THAT bad, but it's still pretty insanely fragile). I have three fully working core memory boards: two 16K*18 and one 32K*18 boards. I had to fix all three of them, since they had bad parts here and there, but it wasn't TOO hard. All of them work similar; there's a hardware state machine that runs a little sequence for reads that do this: read the word, then write the same data back (since reading core is destructive). I successfully dumped the data that was sitting on all three of my core boards; the 16K boards were repaired and put in stock as spares apparently, and just had a 0101010101 pattern, while the 32K board contained actual NASA code! I dumped it but lost 256 words of data, unfortunately. That board had some problems with reading/writing because there was a bad transistor in the X driver, and there was a bad TTL chip. All of them had bad tantalum caps that I had to replace; the 32K board kept randomly drawing enough power to trip the current limit on my power supply every few hours, so I finally found it and replaced the cap which fixed that. The 32K board is extremely "advanced', compared to the 16K boards which are more traditional. The 32K board only has a single X and single Y driver instead of a bunch of each. All of them have a forest of transistor arrays, diodes, and pulse transformers to do selection because it saves a ton of hardware this way. I have a dir on my website with all the stuff I did on it and if there's interest I can make a video showing off my rig and how I tested the memory. I had schematics I drew for the boards but I think I might've lost them. there's some PDFs in there that give esoteric details on the care and feeding of core memory. http://blog.kevtris.org/blogfiles/corememory/

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Core Memory Purchase
by John Sully 02 Dec '15

02 Dec '15

I'm planning to resurrect some old core memory as a hobby project. I was wondering if anyone with experience on getting this memory working could provide some insights on what I should look for. EBay seems to have a large number of expensive ones that don't appear to be in working order - along with some much cheaper (relatively speaking) russian made stacks.

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Festivus - Who's going?
by Herb Johnson 02 Dec '15

02 Dec '15

Herb Johnson - sat late morning -- Herbert R. Johnson, New Jersey USA http://www.retrotechnology.com OR .net

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Re: [vcf-midatlantic] Festivus - Who's going?
by James Garland 02 Dec '15

02 Dec '15

> Put your name on the list and approximate arrival time. > > 1. Jeff Brace 10:30AM Saturday (Staying all weekend) > 2. Evan Koblentz > 3. Dean Notarnicola 11:00 Sat. only > 4. Bill Degnan TBD > 5. Bill Dudley and Xiulan Zhao (not sure of arrival time -- mid-afternoon > Sat?) > 6. Kelly L and Ann 11:00 Sat. only > 7. Steven Toth (mid morn Saturday, all weekend probably). > 8. Tom Hornberger - around 11 on Sun > 9. Dave Riley (noonish Saturday until noonish Sunday) > 10. Connor Krukosky > 11. Ian Primus > 12. Bob Murphy 11:30 Sat - (probably just a cameo to drop off gear) > 13. Chris Fala (both days, Sat. AM - time uncertain) > 14. Jonathan + Amy, 1100 SAT - SUN > 15. Neil Cherry around 3PM (Saturday only) > 16. Bill Dromgoole Saturday about 12:00 to 1:00 and Sunday > 17. James & Eric Garland ~11AM Sunday > 18. > 19. > 20.

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Re: [vcf-midatlantic] Vaxman
by VAXman＠tmesis.org 01 Dec '15

01 Dec '15

David Hoelzer via vcf-midatlantic writes: >Sorry to bother you listmates=E2=80=A6 > >Vaxman, I=E2=80=99d really appreciate it if you would reach out and = >explain to me why I suddenly have a PayPal payment dispute from you but >= no other emails to explain it. I tried to reach you directly but your >= listed email address bounces. Sorry, my wife and I were reviewing the PayPal for the yearly upcoming tax season when she asked me what cybersecurity was. I, for the life of me, didn't recall. Now that you've contacted me, I recall this. Sorry but I couldn't find any other email referneces to cyber-security. I'll remove the dispute immediately.

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Re: [vcf-midatlantic] New web site is live
by Evan Koblentz 01 Dec '15

01 Dec '15

> There's gonna be a VCF _West_ this year? Shh, don't tell anyone. :) It will not be this year (which ends in 30 days). I can't say more until some business things are settled.

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