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Vintage Computer and Technology Swap Meet - Wall, NJ - June 22, 2024

by Jeffrey Brace

Same place as last year in the big parking lot across from Brookdale and down the street from InfoAge Science and History Museums. We have the Southern Monmouth County Firehouse museum selling food and drinks in the middle. This is a fundraiser for both museums (VCF and Firehouse museum) which are both part of InfoAge. All the info is here: https://vcfed.org/vcf-swap-meet/ Thanks! Jeff Brace VCF Mid-Atlantic Event Manager Vintage Computer Federation is a 501c3 charity

6 months, 2 weeks

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Re: Double Density 3.5" Floppy Disks

by Bill Gunshannon

On 5/6/2024 2:28 PM, Wayne S via cctalk wrote: > You do need a very strong magnet. I’ve put 3.5 floppies on top of > a mag tape demagnitizer ( not technically called that, but you know > what i mean) and it had no effect at all. I could still read them fine > in my pc. I surmised that the magnetic field generated was not strong > enough to get through the plastic disk shield. Gave up after that. And yet, I have a cheap Radio Shack tape degauzer and it erases 3.5" disks just fine. I do it all the time whenever I have one that refuses to reformat. Quick pass over the degauzer and they usually work fine. If not, time to toss them. As for 720K disks I bought a box of new ones (12 boxes actually) several years ago on eBay and expect they will out last me. Especially now that I am moving everything to Goteks. bill

6 months, 2 weeks

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Netflix Series: American Conspiracy/Octopus Murders

by Jonathan Katz

Hey everyone, My better half recently turned this on and also a podcast with the creator/director. They mentioned they visited "someone" with a working VAX 11/780 to get b-roll footage for the movie. Which one of us was it? :D In all seriousness, it would be fun to try and get a vintage copy of the PROMIS software running on something (I assume it was VAX/VMS in its original incarnation, but many other screenshots show SNA/greenscreen implementations.) Cheers, all! -- -Jon +44 7792 149029

6 months, 2 weeks

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Re: Altair 8800 50th birthday...

by Smith, Wayne

I looked up the Jan. 1975 issue of Popular Electronics in the Copyright Office's Periodicals Digest. It was published on Nov. 19, 1974 if you are looking for an actual anniversary date. -W > On Saturday, April 27th, 2024 at 07:14, Bill Gunshannon via cctalk < > cctalk(a)classiccmp.org> wrote: > > > > Magazine cover january, and into 1975 the revolution. So I'd say > > > all > > > > I had that magazine. Wish I hadn't thrown it away oh so many years > > ago. > > This one? > > https://urldefense.com/v3/__https://archive.org/details/197511PopularE > lectronics__;!!AQdq3sQhfUj4q8uUguY!jsVD6bkUUnjpF4d8AeRUKyiCW6qk8LAqFsj > dYW5cjAK-kOsMp32O4FfrPI5l1lqnTNp6sXQsHpX35FsPAzYDMIHhl-uy-NSC5w$ > > The Doctor [412/724/301/703/415/510] > WWW: > https://urldefense.com/v3/__https://drwho.virtadpt.net/__;!!AQdq3sQhfU > j4q8uUguY!jsVD6bkUUnjpF4d8AeRUKyiCW6qk8LAqFsjdYW5cjAK-kOsMp32O4FfrPI5l > 1lqnTNp6sXQsHpX35FsPAzYDMIHhl-u9z1M8kw$ > Don't be mean. You don't have to be mean > https://urldefense.com/v3/__https://vintagecomputer.net/altair-poptronics.c… (Jan and Feb)

6 months, 3 weeks

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Re: 5,34 Petaflop System Cheyenne

by Ali

>Fairly sure you could find something to run Doom >that uses less than 1.7MWBut what's the point of buying this monstrosity if not to play Doom? It is like SEVEN years old. ;)

6 months, 3 weeks

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CP/M

by Murray McCullough

I came across an article that said CP/M came out in April 1974. I remember using this OS in the microcomputer world in the late 70’s; early 80’s. It came from PL/M, (Programming Language for Microcomputers) later renamed CP/M(Control Program for Microcomputers). I’m not sure what its legacy is though as far as I can recall it was wrapped up in litigation for quite some time. It was used in the 8-bit world but not sure what it's role was in the early PC world! Happy computing, Murray 🙂

6 months, 3 weeks

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IBM 360

by Murray McCullough

I had not realized the IBM 360 was 60 yrs. old this month. I worked on such a computer in the late 60s in Toronto. What one could do with 8 Kbytes of ram was remarkable! Happy computing Murray 🙂

6 months, 3 weeks

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Diablo Model 40 Series - Disturbed head positioning

by Dominique Carlier

Hello everyone I need your help to identify an issue on my Diablo Model 40 Series. I don't know where to look, it's so vast ! Here's the problem: When RUN is activated, the drive begins its spin up and simultaneously deploys the heads (normal) but instead of stabilizing them, the Head Positioner receives a burst of reverse/forward micro signals. The heads "vibrate", this creates an audible frequency "BRRRRRRRRRRRRRRRRRR", and it is infinite, the heads are never loaded and the drive never reaches READY. At first I thought that perhaps the track zero sensor was defective or something of the same order but when I disengage RUN mode, the drive unloads the heads and they should be in a fixed position, here they continue to reverse/forward but more slowly than in RUN mode. Because the heads continues to mess around even in unload mode, this a priori excludes alignment problems. Here is a video of that issue: https://youtu.be/HzzxLnSdEOg Other information, if I cut the power while the drive is in RUN mode, it does not do an emergency retraction of the heads, related problem? I was hoping for a power supply problem but all the voltages and even on the main board cage seem ok (with a multimeter). If one of you had already encountered this problem of lack of head stabilization and continuous reverse/forward on this type of drive? Thanks ! Dominique

6 months, 3 weeks

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MS-DOS source code

by wrcooke＠wrcooke.net

Some may find this interesting. Microsoft has released the source for MS-DOS versions 1.25, 2, and 4. https://github.com/microsoft/MS-DOS Will Grownups never understand anything by themselves and it is tiresome for children to be always and forever explaining things to them, Antoine de Saint-Exupery in The Little Prince

6 months, 3 weeks

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Re: Diablo Model 40 Series - Disturbed head positioning

by Dominique Carlier

Hi Don ! Good suggestion, these microswitches are used to indicate that the heads are completely retracted. Unfortunately, that would have been too simple, both microswitches work perfectly :-/ On 30/04/2024 19:43, D. Resor wrote: > What is the purpose of the two microswitches seen in the upper right > of the video view? > > Could one or both of those be intermittent? Have they been tested for > continuity/intermittence with an analog VOM? > > Don Resor > > -----Original Message----- > From: Dominique Carlier via cctalk <cctalk(a)classiccmp.org> > Sent: Tuesday, April 30, 2024 8:47 AM > To: General Discussion: On-Topic and Off-Topic Posts > <cctalk(a)classiccmp.org> > Cc: Dominique Carlier <dce(a)skynet.be> > Subject: [cctalk] Diablo Model 40 Series - Disturbed head positioning > > Hello everyone > > I need your help to identify an issue on my Diablo Model 40 Series. I > don't know where to look, it's so vast ! > > Here's the problem: > When RUN is activated, the drive begins its spin up and simultaneously > deploys the heads (normal) but instead of stabilizing them, the Head > Positioner receives a burst of reverse/forward micro signals. The > heads "vibrate", this creates an audible frequency > "BRRRRRRRRRRRRRRRRRR", and it is infinite, the heads are never loaded > and the drive never reaches READY. > > At first I thought that perhaps the track zero sensor was defective or > something of the same order but when I disengage RUN mode, the drive > unloads the heads and they should be in a fixed position, here they > continue to reverse/forward but more slowly than in RUN mode. > Because the heads continues to mess around even in unload mode, this a > priori excludes alignment problems. > > Here is a video of that issue: > > https://youtu.be/HzzxLnSdEOg > > Other information, if I cut the power while the drive is in RUN mode, > it does not do an emergency retraction of the heads, related problem? > I was hoping for a power supply problem but all the voltages and even > on the main board cage seem ok (with a multimeter). > > If one of you had already encountered this problem of lack of head > stabilization and continuous reverse/forward on this type of drive? > > Thanks ! > > Dominique >

6 months, 3 weeks

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