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Xerox Alto Restoration

Posted: Tue Jun 21, 2016 4:46 pm
by josehill
Via OSNews comes word of a restoration project involving a Xerox Alto computer.

It'll be interesting to follow the videos as they work through the project. Although these are linked from the articles mentioned above, to guard against bitrot I'll share the first couple of videos here, too:


Re: Xerox Alto Restoration

Posted: Tue Jun 21, 2016 4:52 pm
by josehill
PS. I also enjoyed the guy's video demonstrating what happens when you try to divide by zero on a Friden STW10 Mechanical Calculator, sold from 1949–1966. Who knew it would be so easy to open a transwarp conduit?

Re: Xerox Alto Restoration

Posted: Tue Jun 21, 2016 5:37 pm
by commodorejohn
This is pretty damn rad. I've been wondering when somebody would finally get around to powering one of these beasts up again, and I hope he makes it at least accessible in a demo capacity like the CHM does with their PDP-1.

Re: Xerox Alto Restoration

Posted: Tue Jun 28, 2016 3:31 pm
by josehill
Part 2: Firing up the monitor

Re: Xerox Alto Restoration

Posted: Tue Jun 28, 2016 4:14 pm
by japes
If anyone lives or visits Seattle, WA you can see an Alto running at the Living Computer Museum. They recently finished restoring a second Alto, but only one is on the floor currently. They have some other Alto projects in the works too. Hint, Ethernet came from PARC at the same time as the Alto, but at the time was 3 mbit - I don't think there was much/any 3 mbit ethernet commercialized, but Alto's are.

It was working, then needed some repair, and it's working again. Here it is:

Re: Xerox Alto Restoration

Posted: Tue Jun 28, 2016 5:56 pm
by robespierre
Well, to be precise, the Alto was never a commercial product you could call up and order. It was used inside Xerox and the rest of them were made available to selected universities as a grant. About 2000 were made.

Re: Xerox Alto Restoration

Posted: Wed Jun 29, 2016 3:56 am
by Shiunbird
josehill wrote:PS. I also enjoyed the guy's video demonstrating what happens when you try to divide by zero on a Friden STW10 Mechanical Calculator, sold from 1949–1966. Who knew it would be so easy to open a transwarp conduit?


This is incredible! =)
Thanks for sharing.

Re: Xerox Alto Restoration

Posted: Wed Jun 29, 2016 4:04 am
by miod
japes wrote:Ethernet came from PARC at the same time as the Alto, but at the time was 3 mbit - I don't think there was much/any 3 mbit ethernet commercialized.

The 3COM Multibus Ethernet board used in Sun-1 and Sun-2 systems was 3MBit. Later models used an Intel board which was 10MBit.

In VME land, the ENP CNC-10 can do 3MBit or 10MBit depending upon jumper settings and resistor packs.

Re: Xerox Alto Restoration

Posted: Wed Jun 29, 2016 8:14 am
by pentium
I feel like they're being a little too selective on their restoration. I mean, the power supplies are one thing but when a monitor is giving you troubles you don't selectively replace caps in a display that old. You replace all of them. It's not that expensive.
Also, many variables are left open on that CRT. While it does have very obvious burn-in they didn't factor in that their high voltage might be low or another circuit might be out of spec, again due to an incomplete recap. I don't even have a CRT checker but they have to know a few people that will. Hanging that off the tube for a few minutes will give them a much better idea of the condition of the tube.
The entire machine feels like it's actually several Alto machines thrown together into one mismatched unit with the most worn out components.
Also, Curiousmarc's videos are indeed amazing. I've been watching him for years.

Re: Xerox Alto Restoration

Posted: Wed Jun 29, 2016 11:29 pm
by nekonoko
pentium wrote:Also, Curiousmarc's videos are indeed amazing. I've been watching him for years.


I actually met him briefly about a year ago - I gave him an extra HP-85 (non-working) so he could restore the one he was working on.

Re: Xerox Alto Restoration

Posted: Thu Jun 30, 2016 11:41 pm
by computron
wheres are last parts ???

eve

Re: Xerox Alto Restoration

Posted: Fri Jul 01, 2016 6:00 pm
by pentium
I believe they're trading parts between the LCM and the CHM. I'm betting you gotta have some serious strings to pull to get in touch with people there to the point you can trade that kind of hardware around.

Re: Xerox Alto Restoration

Posted: Sat Jul 02, 2016 10:18 pm
by kjaer
miod wrote:The 3COM Multibus Ethernet board used in Sun-1 and Sun-2 systems was 3MBit. Later models used an Intel board which was 10MBit.


No, the 3Com board was 10base. 3 Mbit was a different board. It's not clear they ever made it out of Stanford.

Re: Xerox Alto Restoration

Posted: Tue Jul 05, 2016 1:28 am
by robespierre
Part 3:


Re: Xerox Alto Restoration

Posted: Tue Jul 05, 2016 1:47 am
by jan-jaap
I recognize the LH Research power supplies. They give me grief in my 4D/70 Professional IRIS as well :(